Asian Marine Biology 10

) ASIAN MAR BIOLOGY 10 ASIAN MARINE BIOLOGY 10 ASIAN MARINE BIOLOGY 10 1993 The Marine Biological Associatio...

Author: Brian Morton

186 downloads 1833 Views 7MB Size Report

This content was uploaded by our users and we assume good faith they have the permission to share this book. If you own the copyright to this book and it is wrongfully on our website, we offer a simple DMCA procedure to remove your content from our site. Start by pressing the button below!
Report copyright / DMCA form

DOWNLOAD PDF

....

)

ASIAN MAR BIOLOGY 10

ASIAN MARINE BIOLOGY 10

ASIAN MARINE BIOLOGY 10 1993

The Marine Biological Association of Hong Kong

Hong Kong University Press *~*~~)!,[~

© Hong Kong University Press 1994 ISBN 962 209 356 6

Printed in Hong Kong by Nordica Printing Company Limited

THE MARINE BIOLOGICAL ASSOCIATION OF HONG KONG The Association was founded on 12 February 1982 with the following objects: (1) To encourage and assist marine biological research and its beneficial applications in Hong Kong.

(2) To provide means of communication among persons engaged in research in the marine sciences and to provide opportunity for them to forgather by the holding of meetings, symposia, conferences or other gatherings. (3) To act as spokesman when required, on behalf of the interests of marine biology in Hong Kong. (4) To co-operate with other scientific bodies and to seek such affiliations as may be appropriate. (5) To promote the understanding of marine biology in the field of education and amongst the general public in Hong Kong.

Membership of the Association is available in six classes: Full Members, Fellow Members, Student Members, Associate Members, Honorary Members and Sustaining Members.

(i) Full Members. Full members shall be persons who are or have been engaged in or directed research in a branch of marine science and who either possess appropriate academic qualifications or because of knowledge and experience occupy positions that ordinarily would, in the opinion of Council, require academic qualifications. (ii) Fellow Members. Fellow members shall be Full Members who in the opinion of Council are distinguished for their research in marine sciences in Hong Kong and will be entitled to use the designation FMBAHK. (iii) Student Members. Student members shall be persons who are studying relevant subjects at postsecondary but not postgraduate level. (iv) Associate Members. Associate members shall be persons who are interested in the objects of the Association, but do not qualify for full membership. (v) Honorary Members. Honorary members shall be persons distinguished for their research in marine science or who shall have rendered meritorious service to the Association. (vi) Sustaining Members. Sustaining members shall be persons, organizations or institutions who wish to support the objects of the Association.

Current annual subscription rates are set out on the application form available from: The Secretary, The Marine Biological Association of Hong Kong, c/o The Swire Marine Laboratory, The University of Hong Kong, Cape d' Aguilar, Hong Kong

THE MARINE BIOLOGICAL ASSOCIATION OF HONG KONG Officers and Council Honorary President

: Dr L.H.Y. Lee, Ph.D., 1.P.

Honorary Vice-Presidents

: Prof. Wang Gungwu, C.B.E., M.A., Ph.D., F.A.H.A. : Prof. R.S.S. Wu, Ph.D.

Council Chairman

: Prof. Brian Morton

Vice-Chairman

: Dr S.T. Chiu

Secretary

: Dr P.M.S. Mak

Treasurer

: Dr R.Y.H. Cheung

Meeting's Secretary

: Dr S.F. Leung

Membership Secretary

: Dr S.Y. Lee

Librarian

: Dr 1.1. Hodgkiss

Members

: Dr K.H. Chiu : Dr R.G. Ong Che : Dr G. Hodgson

Registered address

: clo The Swire Marine Laboratory, The University of Hong Kong, Cape d' Aguilar, Hong Kong

ASIAN MARINE BIOLOGY Editor Prof. Brian Morton, Department of Zoology and The Swire Marine Laboratory, The University of Hong Kong, Hong Kong Business Editor Dr R. Y .H. Cheung, Department of Biology and Chemistry, City Polytechnic of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Editorial Board Prof. C. Birkeland, University of Guam Marine Laboratory, UOG Station, Mangilao, Guam 96913, USA Dr Y.H. Chien, Department of Aquaculture, National Taiwan College of Marine Science and Technology, Keelung, Taiwan Dr T.E. Chua, International Center for Living Aquatic Resources Management (lCLARM), MC PO Box 1501, Makati, Metro Manila, Philippines Dr L.G. Eldredge Pacific Science Association, PO Box 17801, Honolulu, HI 96817, USA Dr Y.B. Go, Department of Oceanography, College of Ocean Science and Technology, Cheju National University, Cheju 590, South Korea Prof. E.D. Gomez, Marine Sciences Center, University of the Philippines, Diliman, Quezon City 3004, Philippines Dr T.J. Lam, Department of Zoology, National University of Singapore, Kent Ridge, Singapore 0511 Dr S.D. Maynard, Marine Option Program, University of Hawaii, Marine Sciences Building, 1000 Pope Road, Honolulu, HI 96822, USA Dr P. Menasveta, Department of Marine Science, Chulalongkorn University, Phya Thai Road, Bangkok 5, Thailand Prof. T. Okutani, Tokyo University of Fisheries, 4-5-7, Konan, Minato-ku, Tokyo 108, Japan. Prof. C.K. Tseng, Institute of Oceanography, Academia Sinica, 7 Nan-Hai Road, Qingdao, People's Republic of China Dr M. Williams, Australian Institute of Marine Science, P.M.B. No. 3, Townsville MC, Queensland 4810, Australia Dr Yu. M. Yakovlev, Institute of Marine Biology, Far East Branch, Russian Academy of Sciences, Vladivostok 690032, Russia

INSTRUCTIONS TO AUTHORS

1.

Submission of manuscripts. Papers should be sent to: The Editor, Asian Marine Biology, The Swire Marine Laboratory, The University of Hong Kong, Hong Kong. The submission of a manuscript will be taken to imply that the material is original and that no similar paper is being, or will be, submitted for publication elsewhere. When accepted, the copyright of a paper becomes the property of The Marine Biological Association of Hong Kong and permission must be obtained to reproduce material from papers published by the Association. Theses and serialized studies should not be submitted.

2.

Manuscripts. Papers should be written in clear, concise English with the minimum number of tables and illustrations. Form and content should be carefully checked before submission to avoid the need for corrections in proof. A charge will be made for changes introduced after an article has been typeset. The text may be arranged as follows: (a) Title. This should be concise, specific and typed on a separate cover sheet together with the name(s) of the author(s) and that of the institution in which the research was carried out. The name of a new genus or species must not be included in the title. A short title, of not more than 40 characters (including spaces), should be provided for page headings. (b) Abstract. This should generally not exceed 200 words and must be intelligible to the reader without reference to the main text. Avoid abbreviations. (c) Introduction, followed by the subject matter of the paper. (d) Materials and methods. (e) Results. (f) Discussion (g) Acknowledgements. (h) References-See Section 6. (i) Illustrations-See Section 4. If the paper is short, it may be preferable not to divide it into sections.

3.

Presentation. Two copies of the typescript should be provided, double spaced throughout (including tables, legends and footnotes) on one side of quarto or A4 paper, with a margin of 2.5 cm all round. Please indicate the position of tables and illustrations in the text; tables and legends for illustrations should be typed separately at the end of the manuscript. All pages should be numbered serially and fastened together securely. Except for short contributions, papers should be divided into sections described by headings. The first subhead will be shouldered, the second italicized shouldered and the third run-on with the copy. An initial capital letter must be used for proper names, the Latin names of orders, families and similar names, but not for anglicized derivatives from Latin names or for English names of plants and animals. Generic and specific names must be underlined. Footnotes should be avoided but if essential, must be indicated by superscript figures in the text and collected on a single page placed at the end of the manuscript. If it is necessary to refer to various passages in the text, please ensure that the relevant manuscript page number is given.

Instructions to Authors

If a new taxon is described, the institution in which the type material is deposited must be indicated together with details of the registration assigned to it. Customary abbreviations will be used. Citations in the text should read (Brown 1975) or Brown and Jones (1975). When a paper has more than two authors, the style Smith et al. (1980) or (Smith et al. 1980) should be used. The convention (Brown 1975a), Brown (l975b) should be used when more than one paper is cited by the same author(s) and published in the same year. Note that these papers should be alphabetized by title, discounting an initial article.

4.

Illustrations. All illustrations will be reduced to a size not exceeding 19 x 14 cm. No illustrations should be submitted which will not fit into an envelope 35 x 47 cm. A metric scale should preferably be included on each illustration. If this is not possible, the magnification (or reduction) should be given in the legend and adjusted after any modification in the size of the illustration. Line drawings are referred to as Fig. 1, Fig. 2, etc., and halftone blocks as Plate I, Plate 2, etc. If a line drawing or halftone plate is composed of more than one SUbject, one should be identified as (A), (B), etc. The name(s) of the author(s) and the number of the figure or plate must be marked on the back of all illustrations, and the orientation of the illustrations indicated. (a) Line drawings. These should be submitted on quarto (28 x 21.5 cm) or A4 (30 x 21 cm) sheets. Drawings should be in Indian ink on tracing linens, Bristol board or faintly blue-lined graph paper. Photocopies of drawings cannot be reproduced satisfactorily, but may in the first instance be submitted, and the original drawing sent if the paper is accepted. Explanations should, as far as possible, be placed in the legend; any necessary lettering on figures should be lightly inserted in blue pencil. Graph curves may be distinguished by use of solid pecked --- or dotted ... lines. The following symbols available to the printer also, can be used for experimentally determined points and for keying in the legends: 0, e, 0, ., ~, . , V, ~. (b) Photographic halftone illustrations. Best quality glossy prints should be submitted of a size capable of reduction rather than enlargement. Photographs should be mounted on white backing board and grouped as they will be reproduced.

5.

Numerical matter. Metric system to be used throughout. Only the minimum of numerical matter essential for clarity should be included.

6.

References. Important: Authors are requested to check the list of references against the text to ensure that: (a) The spelling of authors' names and the dates given are consistent. (b) All authors quoted in the text are included in the list of references. If more than one reference by the same author(s), published in the same year is cited, use, a, b, etc., after the year in both text and list, e.g., 1963a. Text citations can be given in either of two ways: (i) Single author: Where more than one reference is given for a single author the publications should be listed chronologically. (ii) Two authors: References for which there are two authors should be arranged first alphabetically then chronologically. For text citations, use both authors' names and the year. Do not use et al. for two author references. (iii) Three or more authors: References with three or more authors should be arranged first alphabetically then chronologically. For all citations in the text it is usually sufficient to quote the surname of the first author, followed by et al. and the date, but for reasons of clarity it may sometimes be necessary to use the names of the first two (or more) authors. ix


Please note that the names of all authors should be given in the list of references and et al. used only in the text. The full title of the paper must be given. Journal titles must also be given in full. The volume number should be followed by the first and last pages of the paper. Include the issue number only when the journal referred to is paginated by issue rather than by volume.

Examples Journal references: Beklemishev, K. V. 1952. Nutrition of predatory intertidal invertebrates and their feeding interrelations with commercial fish and birds. Trudy Vsesoyusnogo Hidrobiologicheskogo Obschestva 5:276-96 (in Russian). Ponder, W.F., Colman, P.H., Yonge, C.M. and Colman, M.H. 1981. The taxonomic position of Hemidonax Morch, 1871 with a review of the genus (Bivalvia: Cardiacea). Journal of the Malacological Society of Australia 3:41-64. Shapiro, D. Y. 1981. Size, maturation and the social control of sex reversal in the coral reef fish Anthias squamipinnis. Journal of Zoology, London 193: 105-28. Tyler, P.A. and Gage, J.D. 1982. The reproductive biology of Ophiacantha bidentata (Echinodermata: Ophiuroidea) from the Rockall Trough. Journal of the Marine Biological Association of the United Kingdom 62:45-56. Book references: Huang, Z.G. and Cai, R.X. 1984. Marine Biofouling and Its Prevention. Beijing: China Ocean Press. (In Chinese) Johnson, R.W. and Ohlhorst, C.W. 1981. Application of remote sensing to monitoring and studying dispersion in ocean dumping. In Ocean Dumping of Industrial Wastes (ed. B.H. Ketchum, D.R. Kester and P. Kilho Park). Vol. 12, Marine science, 175-9l. New York and London: Plenum Press. (Note: 'ed.' here means 'edited by', hence never 'eds.') King, C.A.M. 1972. Beaches and Coasts. London: Edward Arnold. Lam, C.W.Y. 1979. The Assessment of Eutrophication in Estuaries: A Review of New Zealand and Overseas Studies. Hamilton Science Centre Internal Report No. 79/38. 44 pp. New Zealand: Ministry of Works and Development. Morton, B. and Tseng C.K., eds. 1982. The Marine Flora and Fauna of Hong Kong and Southern China. 2 vols. Proceedings of the First International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1980. Hong Kong: Hong Kong University Press. (Note: 'eds.' here means 'editors') Tsi, C.Y. and Ma, S.T. 1982. A preliminary checklist of the marine Gastropoda and Bivalvia (Mollusca) of Hong Kong and southern China. In The Marine Flora and Fauna of Hong Kong and Southern China (ed. B. Morton and C.K. Tseng), 431-58. Proceedings of the First International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1980. Hong Kong: Hong Kong University Press. Unpublished material: Cortes-Zaragoza, E. 1983. Morphometrics and relative abundance of tunas (Perciformes: Scombridae) caught off Darigayos Cove, La Union. 85 pp. M.Sc. thesis, University of the Philippines. Shin, P.K.S. 1986. Effects of a spill of bunker oil on the marine biological communities in Hong Kong. Paper presented in the International Symposium on Environmental Pollution and Toxicology, 9-11 September 1986, Baptist College, Hong Kong. x


7.

Proofs. One set of galley proofs and the original manuscript will be sent to the author. Corrections should be made on the marked copy which should be returned with the original manuscript to: The Editor, Asian Marine Biology, The Swire Marine Laboratory, The University of Hong Kong, Hong Kong. Page proofs will not normally be sent to the author.

8.

Copyright/Offprints. Authors submitting a manuscript do so on the understanding that if it is accepted for publication, copyright shall be assigned to The Marine Biological Association of Hong Kong. Offprints may be ordered at the proof stage. The Association will not put any limitation on the personal freedom of the author to use material contained in the paper in other works which may be published elsewhere.

9.

Important. Whenever a Latin name is employed it must be followed by the authority, e.g., Anomalocardia squamosa Lamarck, on first usage in the paper. Authors are reminded that: (a) Descriptions of new taxa must follow the Rules and Recommendations of the International Commission on Zoological (or Botanical) Nomenclature. (b) All primary types of new taxa must be quoted in the paper. (c) Vouchers specimens of each taxon discussed should be deposited in a recognized institutional collection and a registration number obtained which should be quoted in the paper.

10. Word-processor disks. All manuscripts must be provided on a floppy disk after the paper has been accepted for publication, in addition to the final printed version. It will speed the publication of your paper if you can send a copy of the text on 360K or 1.2M 5.25" disk for IBM personal computer, or compatible, or 720K or 1.44M 3.5" disk for Apple Macintosh computer. The disk will be returned to you. (a) Ensure that the disk you send contains only the final version of the paper and is identical to the typescript. (b) Label the disk with author's name, title of paper, machine and the word-processing programme used. (c) Supply the file as a fully formatted 'text only', WordS tar (4 or above) or WordPerfect (4 or above) file on IBM personal computer or a Microsoft Word (3 or above) file on Apple Macintosh computer. (d) Use no special formatting characters. (e) Comply as closely as possible with the general Instructions to Authors.

xi

EDITORIAL From 9-11 September 1992, The Marine Biological Association of Hong Kong and the Agriculture and Fisheries Department and the Environmental Protection Department of the Hong Kong Government coorganized a Colloquium on Red Tides in Hong Kong and South China, attended by some thirty scientists from Hong Kong, China and Great Britain. A total of 14 papers were presented, some of which are, following peer review, published in this issue of Asian Marine Biology. The growing problem of red tides in the coastal waters of the South China Sea is now attracting a greater level of concern. The Second International Conference on the Marine Biology of the South China Sea was convened in Guangzhou from 3-7 April 1993. Organized by the Marine Biology Research Station at Dayawan of The South China Sea Institute of Oceanology, Chinese Academy of Sciences, and the Guangdong Society of Oceanology and Limnology, in conjunction with The Marine Biological Association of Hong Kong, the Conference was a great success. Its success was slightly marred by the fact that very few delegates from countries other than China and Hong Kong could attend. Notwithstanding, there were some ninety delegates, with Hong Kong represented by 23 members of the Association, both scientists and students. The few other delegates were from the United Kingdom (2), the United States (1) and Taiwan (1). The real achievement of the Conference, however, was its organization, being convened in an international hotel and with all talks being in English and, in general, well-presented. The range of talks was extremely wide but I do not consider this to be a particular problem, it probably being more appropriate for such a meeting that delegates obtain a broader insight into the marine biology of the South China Sea. One day, specialist meetings on the South China Sea may be convened, as with the Red Tide Colloquium, but it seems sensible that the triannual meeting be broad-based. The next Conference will be held in Hong Kong in 1996. The Proceedings of the 1993 Conference will be published, after the selected papers have been refereed, by Ocean Press, Beijing. Artificial Reefs have been built in the sea in the United States and Japan and an experimental one made from pulverized fuel ash (PFA) was established by The University of Southampton, UK, three years ago. Now Hong Kong is to have its first such structure and made, like the Southampton model, from experimental PFA/cement mixes. Hong Kong is losing its natural shoreline and shallow subtidal marine habitats fast as a consequence of coastal reclamation. The pace of such reclamation has been stepped up in recent years, particularly with regard to the Port and Airport Strategy (PADS) and the development of the new airport at Chek Lap Kok and the associated reclamation of West Kowloon and North Lantau. Completion of this project will mean that some 18% of Hong Kong's shoreline has been reclaimed. The consequences of such developments and of the sand dredging that is needed to complete them are that Hong Kong will have lost coastal zone areas which are the habitat of mangroves, sea grasses and corals, which are, in turn, the most delicate of our marine communities. Nursery areas for fish and prawns will also be lost. The aims of the Artificial Reef project are, therefore, to ascertain whether such structures can replace reclaimed habitat, particularly for corals, and whether or not they do act as either fish aggregating or fish breeding devices. It is, however, also important to know whether the potentially toxic trace metals found in the PFA are either leached out during immersion or are sealed into the fabric of the reef by the cement, the encrusting organisms and by the hardening effects of seawater. If the experiment works and it can be proven that trace metals are not released from the blocks, it is possible that Artificial Reefs of PFA may become a feature of Hong Kong's coastal wa"ters. Two fatal shark attacks occurred in Hong Kong's eastern waters in early June 1993. Recent fatal shark attacks were in 1979 and 1991 although it is possible that the occasional 'disappearance' of

Editorial

swimmers is also attributable to such attacks. The culprit(s) in 1993 seem to have been tiger sharks that moved into Hong Kong's waters in early summer. The same is possibly true of the 1979 and 1991 cases since these occurred in August and June, respectively. The Hong Kong government seems to have been at quite a loss to know what to do, in terms of public safety at swimming beaches, about such attacks, but one local newspaper sponsored the employment of a shark 'expert' or 'hunter' to kill what he believed to be a rogue shark, malevolently stalking human beings. This has possibly sold newspapers but it also created a local feeling of paranoia reminiscent of the movie 'Jaws' and drowned any scientific debate on possible means to manage at least some local beaches so that they are shark-free. Hong Kong does not have any shark researchers and, in their absence, calls for sensible experts to be brought in from overseas, namely Australia, have been ignored and attention focused instead on the hunter. I believe such hunting is futile since one can never be sure of the true identity of the attacker, nor if there is only one 'rogue' (which I do not believe in anyway). To make Hong Kong's shores safe from shark attack, we would have to kill all of them in the South China Sea. It is almost certainly true that such attacks are 'accidents' waiting to happen, the swimmer being in the wrong place at the wrong time, that is Hong Kong's eastern waters and early in the morning. The analogy is with the chance of being hit by lightning. This, I know, is of no solace to the grieving families of the victims but the truth of the matter is that in sub-tropical Hong Kong, probably anywhere, one has to realize that when you enter the sea you are entering the habitat of a significant predator. Whatever we do in life involves us making decisions about the risks involved. Ultimately the responsibility for swimming in shallow, sub-tropical, seas is our own but, notwithstanding, it does seem incumbent upon the government to try and ensure that at least some of the most popular beaches are shark-free, if only during the summer when many people enjoy swimming. At the 11 th Annual General Meeting of The Marine Biological Association of Hong Kong, the following were either elected or re-elected to office: Dr. S.T. Chiu (Vice-Chairman), Dr P.M.S. Mak (Secretary), Dr R.Y.H. Cheung (Treasurer), Dr. S.Y. Lee (Membership Secretary), Dr R.G. Ong Che (Councillor) and Dr K.H. Chiu (Councillor). Stepping down as Vice-Chairman of the Association is Dr N.Y.S. Woo who has served in this capacity since 1990. Grateful thanks are extended to Dr Woo for his service to the Association. Welcomed onto the Editorial Board of Asian Marine Biology is Dr M. Williams who has replaced Dr J.T. Baker upon his retirement as Director of the Australian Institute of Marine Science and Dr L.G. Eldredge, Executive Secretary of the Pacific Science Association, Hawaii.

Brian Morton

xiv

CONTENTS

The Marine Biological Association of Hong Kong ................................................................................

v

Asian Marine Biology-Editorial Board .................................................................................................. vii Instructions to Authors ............................................................................................................................... viii Editorial ........................................................................................................................................................ xiii Fouling polychaetes of Hong Kong and adjacent waters Wang Iianjun and Huang Zongguo .................................................................................................... . Four new species of Cumacea from Peter the Great Bay, Sea of Japan Ludmilla A. Tzareva and Stella V. Vassilenko ...................................................................................

13

The effects of physical factors and grazing by limpets on the colonization, growth and composition of intertidal algae on a rocky shore at Cape d' Aguilar, Hong Kong I.H. Liu ................................................................................................................................................... 27 Biosynthetic conditions and properties of Streptomyces sp. chitinase isolated from the mangrove rhizosphere Zheng Zhicheng, Zhou Meiying and Zheng Tianling ........................................................................

41

Marine enclosure ecosystem experiments to study red tide mechanisms and processes in Xiamen Harbour, China Lin Yu, Zhuang Dongja, Tang Senming and Chen Xiaolin ..............................................................

45

Some coral reef pontoniine shrimps from Vietnam A.I. Bruce ...............................................................................................................................................

55

Assessing the limiting factors of red tide by bottle bioassay K. C. Ho and /,1. Hodgkiss ...... .................................................................................................... 77 Effect of experimental harvesting on kelp regrowth and on the structure of the shallow-water communities of Bering Island (Commander Islands) V. V. Oshurkov and E.A. Ivanjushina................................................ ................................................... 95 Barnacles as biomonitors of trace metals in the coastal waters near Xiamen, China P.S. Rainbow, Huang Zongguo, Yan Songkai and Brian D. Smith ................................................. 109 Larval development of Eupentacta fraudatrix (Holothuroidea: Dendrochirota) Igor Yu. Dolmatov and V. V. Yushin .................................................................................................... 123

Asian Marine Biology 10 (1 993): 1-12

FOULING POL YCHAETES OF HONG KONG AND ADJACENT WATERS Wang Jianjun and Huang Zongguo Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China

Abstract From 1980 to 1989, 372 samples of fouling organisms were collected from ships, piers, buoys and mariculture cages in Hong Kong and adjacent waters. Seventy species of polychaetes have been recorded. Hydroides elegans, H. dirampha, H. inornata and Pomatoleios kraussii were the dominant species. These are also major biofoulers in Hong Kong, the maximum recorded wet weight of these organisms being 20.34 kg·m- 2 • The distributions of the species in relation to tidal level, salinity gradient and degree of tidal exposure were studied and corresponding indicator species for these different environmental conditions identified.

Introduction There have been few studies of Hong Kong's polychaete fauna. Mak (1980) and Shin (1982) identified species from corals and subtidal sediment habitats, respectively. Hutchings (1990) investigated Hong Kong's Terebellidae and Mackie (1990) the Poecilochaetidae and Trochochaetidae. Mackie and Hartley (1990) described a new species of Prionospio from Hong Kong and Mackie (1991) a new species of Scoloplos. Ohwada (1992) has also described a new local species of Aglaophamus. Although there have been a number of studies of Hong Kong's marine fouling community (Vrijmoed 1973; Greene and Morton 1976; Vrijmoed et al. 1986; Huang and Mak 1982; Huang et al. 1992), there is little known about fouling polychaetes in particular and some of which, e.g., Hydroides elegans (Mak and Huang 1982), are significant. This paper focuses attention on Hong Kong's fouling polychaetes.

Materials and methods From 1980 to 1989, 372 samples of fouling organisms were collected from 64 sites in Hong

Kong and adjacent waters (Fig. 1), including the high, middle and lower tidal levels of the pilings of 29 piers; the water lines, sides and hulls of 22 ships; the water lines, sides, anchor chains and anchoring blocks of 17 buoys; and the cages and rafts at 10 mariculture zones. Such stations are spread all over the estuarine, transitional and marine zones of Hong Kong's waters, as proposed by Morton (1982). Additional samples were collected from the Pearl River estuary. The polychaete communities were analysed, to identify the species, their significance as foulers and their relationship to salinity, tidal level and degree of tidal exposure.

Results Species Seventy species of fouling polychaetes were recorded from the 372 samples obtained during this study, belonging to sixteen families. There were twenty tubiculous and sedentary species, including ten species of Sabellidae and Terebellidae living in membranous tubes and 10 species of Serpulidae and Spirorbidae in calcareous tubes (Table 1). Twelve species were not identified.

J.J. Wang & Z.G. Huang

JULY

30'

20'

A test panels

22" 10'

•

fixed piers

.;.

buoys

-c:: cages and rafts

b

vessels

4 4

,

ESTU~RINE

0

~

a

TRANSITIONAL OCEANIC '----------------------------~~----------------

Fig. 1. A map of Hong Kong and adjacent waters showing the sampling sites and; above; salinity profiles for the Pearl River in January and July. 1. Hunan buoys, 2; Shajiao buoys, 3; Shajiao pier, 4-19; Lingding buoys, 20-21; Chiwan buoys, 22; Shekou pier, 23-27; Deep Bay buoys, 28; Tsim Bei Tsui pier, 29; Lau Fau Shan pier, 30; Tap Shek Kok pier, 31; Tai Lam Chung pier, 32; Tsing Yi pier, 33; Tung Chung pier, 34; Tung Chung cages, 35; Tai 0 pier, 36; Cheung Chau pier, 37; Hong Kong boats and ships, 38; Kennedy Town pier, 39; Tsim Sha Tsui pier, 40; Central District pier, 41; North Point pier, 41; North Point pier, 42; A Kung Ngam pier, 43; Tai Tam pier, 44; Tai Tam buoys, 45; Tai Tam panels, 45a; Cape d'Aguilar rocks, 46; Aberdeen pier, 47; Picnic Bay cages, 48; Shipwreck buoys, 49; Pak Sha Wan cages, 49a; Sai Kung pier, 50; Tap Mun pier, 50a; Tap Mun cages, 51; Wong Shek pier, 52; Wu Kai Sha pier, 53; Chinese University pier, 54; Sam Mum Jai pier, 55; Tai Mei Tuk cages, 56; Tolo Harbour buoys, 57. Lo Fu Fut cages, 58; Kat 0 cages, 59; Kat 0 pier, 60; Kat 0 panels, 61; Obei Tang cages, 62; Ping Chau pier, 63; Nanao pier, 64; Yantian pier.

2

Table 1. Fouling polychaetes recorded from Hong Kong and adjacent waters. Species

Occurrence times

Numbers

Tidal levels

Salinity tolerances

Sites

Cirriformia capensis

3

111

M-S

h

51,64

C. tentaculata

5

33

L

e

39-42

2

L

h

63

L

e

38

70

H-S

h, e

2

S

e

6

H-L

h, e

CIRRATULlDAE

OPHELLlDAE Polyophthalmus pictus PHYLLODOCIDAE Eumida sanguinea Eulalia viridis

21

Phyllodoce sp. Genetyllis castanea

3

16, 18, 20-21, 32, 37-42, 49, 51-52 55 41-42, 49a

HESIONIDAE Micropodarke dubia

H

53

SYLLlDAE Myrianida cf. pachycera

32

Syllis amica

49a

3

"Tl

0

c

3" co "0

0

-
70%), and on the middle shore, where patches of Hildenbrandia prototypus Nardo, Branchytrichia maculans Gomont and Gomontia sp. covered some 10% of the rock surface. Limpets, the predominant herbi vores of the shore, were present year round.

General methods and cage structure The experiments and sampling were carried out at both lower and higher levels of the middle shore,

The effects of grazing by Gel/ana and Patel/oida

HONG I4=3=2 Time No. 2 3 Time Nov. Dec. Jan. Mean % cover 17.07 22.42 22.17 S.N.K. tests (p = 0.05) on time (numbers as above) 4=5=6=7>1=2=3

P

F

4 Open cages 14.59

5 Mar. 36.13

6 Apr. 31.98

7 May 31.85

35

J.H. Liu

Table 4. Two-factor analysis of variance of algal percentage cover for each month at + 2 m C.D. with different grazing treatments (*indicates a significant difference). Source of variation Treatment Time TxT Error Total

DF 2 6 12 42 62

P

F

Seq SS

Adj Ms

109975.5 993.7 827.4 364.7 112161.3

54987.7 165.6 69.0 8.7

Significant

0.000 0.000 0.000

6333.14 19.07 7.94

Treatment No. 1 2 3 3 Gellana Open cages Grazing Ungrazed treatment 11.37 15.80 79.55 Mean % cover S.N.K. tests (p = 0.05) on grazing treatment (numbers as above) 1> 2= 3 Time No. 2 3 Time Nov. Dec. Jan. 33.33 34.33 36.33 Mean % cover S.N.K. tests (p = 0.05) on time (numbers as above) 4>1=6=2=7=3 4=5 1=2=3=5=6=7

4 Feb. 45.33

5

6 Apr. 33.33

Mar. 38.67

7 May 34.78

Table 5. Two-factor analysis of variance of algal chlorophyll a content for each month at + 1 m C.D. with different grazing treatments (* indicates a significant difference). Source of variation

DF

Seq SS

Treatment Time TxT Error Total

3 6 18 56 83

349.363 43.512 83.476 19.726 496.078

Adj Ms 116.454 7.252 4.638 0.352

F

P

330.60 20.5 13.17

0.000 0.000 0.000

2 Treatment No. 1 3 9 Patelloida Grazing Ungrazed 10 Gel/ana treatment Mean chlorophyll a content 6.35 1.41 2.41 S.N.K. tests (p = 0.05) on grazing treatment (numbers as above) 1>4=3=2

Time No. 2 Time Nov. Dec. Mean chlorophyll a content 1.94 1.81 S.N.K. tests (p = 0.05) on time (numbers as above) 3=4=5=6=7 5=4=7>1=2 1 =2 =3 6>2 6 =1 36

Significant

4 Open cages 1.41

3 Jan.

4 Feb.

5

6

Mar.

Apr.

7 May

2.57

3.51

3.64

3.34

3.44


Table 6. Two-factor analysis of variance of algal chlorophyll a content for each month at + 2 m C.D. with different grazing treatments (* indicates a significant difference). Source of variation

OF

Seq SS

Treatment Time TxT Error Total

2 6 12 42 62

776.941 453.420 348.185 40.946 1619.491

Adj Ms 388.471 75.570 29.015 0.975

experimental period, but did reduce biomass. Such results are consistent with the findings of other authors (Lubchenco 1978~ Lubchenco and Gaines 1981 ~ Steneck 1982). Encrusting algae are, probably, more resistant to the effects of grazing by gastropods (Lubchenco and Cubit 1980~ Slocum 1980; Kitting 1980). Cubit (1984) found that a partial reduction in herbivory resulted in the development and persistence of a dense cover of algae throughout the summer months, as well as an overall increase in algal abundance during other times of the year. This author has also indicated that seasonal fluctuations in algal abundance result from variation in rates of algal production rather than from changes in either absolute rates of algal loss to herbivory or physical stresses. Seasonal fluctuations in the abundance of algae can be correlated with the degree of habitat exposure to the physical stresses of desiccation, solar radiation and high temperatures experienced during low tide. Physical factors have a great impact on algal biomass, especially at higher tidal levels on the

Significant

0.000 0.000 0.000

398.47 77.52 29.76

Treatment No. 1 2 3 Gel/ana Ungrazed Grazing treatment 10.22 2.78 Mean chlorophyll a content S.N.K. tests (p = 0.05) on grazing treatment (numbers as above) 1>2 = 3 2 Time No. Time Nov. Dec. Mean chlorophyll a content 2.45 2.89 S.N.K. tests (p = 0.05) on time (numbers as above) 4>5>1=2=6=7 2=3=6=7 4>5=3>1

P

F

3 Open cages 2.76

5

Jan.

4 Feb.

Mar.

6 Apr.

7 May

5.26

10.72

7.24

4.55

3.63

3

shore, where conditions are harsher. In the ungrazed plots at + 2 m C.D., algal biomass, in terms of chlorophyll a (J..Lg·cm- 2 ), showed a distinct seasonal pattern. The pattern has also been statistically identified for both algal percentage cover and chlorophyll a at this level on the shore (Tables 4 and 6). Algal biomass was higher during the cooler months of the year. Such a seasonal pattern is thought to be caused by variations in rates of algal production, which are related to seasonal changes in the physical environment (Hodgkiss 1984; Ho 1986), particularly with regard to temperature (Underwood and lernakoff 1984) and degree of wetting (John son et al. 1974; Quadir et al. 1979; Underwood and lernakoff 1984) during the daylight hours which, in turn, depend on weather conditions, variations in wave height and tidal patterns. In summer, high temperatures and desiccation create lower rates of algal production than in winter. An increased abundance of algae during the winter is unlikely to result from either a seasonal decrease in limpet population density or an interruption of grazing 37

J.H. Liu

activities, because there is at this time simultaneous increases in growth rate and reproductive activity (Liu 1992). Physical factors have little impact on the biomass of the encrusting alga Hildenbrandia prototypus at + I m C.D., where physical conditions are more benign. The biomass and percentage cover of Hildenbrandia prototypus in the un grazed plots at + 1 m C.D. generally increased throughout the experimental period. Acrochaetium robustum, Bangia juscopurpurea, Porphyra dentata and VIva lactuca Linnaeus were, moreover, present in winter and early spring in all grazer-excluded plots at + 2 m C.D., but also disappeared in May. Physical stress is thought to prevent the establishment of the algae during the summer. Such results suggest strongly that a harsh physical environment, especially during low tide, i.e., desiccation, high temperature and light intensity, are important in inhibiting the colonization and growth of intertidal macroalgae in Hong Kong. It was not anticipated that Porphyra dentata would occur in the three Cellana toreuma enclosed cages, even in small amounts « 20%), between January and March. Other ephemeral macroalgae did not. This is thought to be caused by: (I) the effects of the cages and (2) a reduced feeding by Cellana toreuma on the sporelings and young stages of this species, caused by their heavy settlement and higher rates of production. Shading, caused by cages, provides protection from desiccation, insolation and high temperatures. Cages also reduce the mechanical stress of wave action (Cubit 1984). Cages may, thus, provide more suitable conditions for the colonization of Porphyra dentata spores inside the cages even under grazing pressure. It is important to note that Porphyra dentata occurred (1) at higher levels on the shore (+ 2 m C.D.); (2) during the cooler months of the year; (3) in greater amounts in ungrazed plots between December and

March and in small amounts in the three Cellana toreuma grazed plots between January and March and (4) not in open plots which could be grazed by all herbivores. Porphyra dentata appeared in the three Cellana toreuma grazed plots one month later than in the ungrazed plots. It can be assumed that their limited elimination from the latter plots resulted from a reduced grazing level on the sporelings of Porphyra dentata. This allowed them to grow into adults when the heavy settlement and higher rates of production of this species occurred during the most suitable periods of the year, particularly under the protection of the effects of the cages. Limpets, in combination with other herbivores, may thus have a profound impact on the colonization and growth of Porphyra dentata on Hong Kong shores. The great differences in terms of algal biomass, species richness and composition between the grazed and ungrazed plots confirm that limpet grazing has a significant impact on the colonization and growth of intertidal algae in hong Kong. The growth of both ephemeral macroalgae and perennial encrusting algae increase when and where physical conditions are more benign, i.e., during the cooler months of the year and at lower levels on the shore. In conclusion, algal colonization and growth are determined primarily by the grazing of limpets, but are also influenced by physical factors modifying the rates of algal growth.

Acknowledgements I would like to thank my supervisors, Dr I.J. Hodgkiss and Prof. Brian Morton for their advice on this study and for the latters critical reading of the first drafts of the manuscript of this paper. This work forms a part of the thesis submitted to The University of Hong Kong for the degree of Doctor of Philosophy.

References Black, R. 1976. The effects of grazing by the limpet, Acmaea insessa, on the kelp, Egregia laevigata, in the intertidal zone. Ecology 57:265-77. 38

Branch, G .M. 1981. The biology of limpets: physical factors, energy flow, and ecological interactions. Oceanography and Marine Biology Annual Review 19:235-380.


Castenholz, R.W. 1961. The effect of grazing on marine littoral diatom populations. Ecology 42:783-94. Chapman, A.R.O. 1973. A critique of prevailing attitudes on the control of seaweed zonation on the sea shore. Botanica Marina 16:80-2. Cubit, J .D. 1984. Herbivory and the seasonal abundance of algae on a high intertidal rocky shore. Ecology 65:1904-17. Farrell, T.M. 1988. Community stability: effects of limpet removal and reintroduction in a rocky intertidal community. Oecologia 75: 190-7. Frank, P.W. 1965. The biodemography of an intertidal snail population. Ecology 46:83144. Haven, S.B. 1973. Competition for food between the intertidal gastropods Acmaea scabra and Acmaea digitalis. Ecology 54: 143-51. Hawkins, S.J. 1981 a. The influence of season and barnacle cover on algal colonization of Patella vulgata exclusion cages. Journal of Experimental Marine Biology and Ecology 61:1-15. Hawkins, S.J. 1981 b. The influence of Patella grazing on the fucoid/barnacle mosaic on moderately exposed rocky shores. Kieler Meeresforschung Sonderheft 5:537-43. Hawkins, S.J. 1983. Interactions of Patella and macroalgae with settling Semibalanus balanoides (L.). Journal of Experimental Marine Biology and Ecology 71 :55-72. Hawkins, SJ. and Hartnoll, R.G. 1983. Grazing of intertidal algae by marine invertebrates. Oceanography and Marine Biology Annual Review 21: 195-282. Hawkins, SJ. and Hartnoll, R.G. 1985. Factors determining the upper limits of intertidal canopy-forming algae. Marine Ecology Progress Series 20:265-71. Hawkins, S.J., Hartnoll, R.G., Kain (Jones), J.M., and Norton, T.A. 1992. Plant-animal interactions on hard substrata in the north-east Atlantic. In Plant-Animal Interactions in the Marine Benthos (ed. D.M. John, S.J. Hawkins and J .H. Price), 1-32. Systematics Association Special Volume No. 46. Oxford: Clarendon Press. Hay, C.H. 1979. Some factors affecting the upper

limit of the southern bull kelp Durvillea antarctica (Chamisso) Hariot on two New Zealand shores. Journal of the Royal Society of New Zealand 9:279-89. HMSO, 1986. The determination of chlorophyll a in aquatic environments, vol. 4. In Methods for the Examination of Water and Associated Materials. Section 2. London: HMSO. Ho, Y.B., 1986. Common intertidal algae of the southren part of Hong Kong Island. Memoirs of the Hong Kong Natural History Society 17:103-6. Hodgkiss, I.J. 1984. Seasonal patterns of intertidal algal distribution in Hong Kong. Asian Marine Biology 1:49-57. Jara, H.F. and Moreno, C.A. 1984. Herbivory and structure in a midlittoral rocky community: a case in southern Chile. Ecology 65:28-38. Jernakoff, P. 1983. Factors affecting the recruitment of algae in a midshore region dominated by barnacles. Journal of Experimental Marine Biology and Ecology 67: 17-31. Jernakoff, P. 1985. Interactions between the limpet Patelloida latistrigata and algae on an intertidal rock platform. Marine Ecology Progress Series 23 :71-8. Johnson, W.S., Gigon, A., Gulmon, S.L. and Mooney, H.A. 1974. Comparative photosynthetic capacities of intertidal algae under exposed and submerged conditions. Ecology 55:450-3. Jones, N .S. 1948. Observations and experiments on the biology of Patella vulgata at Port St. Mary, Isle of Man. Proceedings and Transactions of the Liverpool Biological Society 56:60-77. Kitting, C.L. 1980. Herbivore-plant interactions of individual limpets maintaining a mixed diet of intertidal marine algae. Ecological Monographs 50:527-50. Lewis, J.R. 1964. The Ecology of Rocky Shores. London: English Universities Press. Liu, J .H. 1992. The ecology of Hong Kong limpets. 201 pp. Ph.D thesis, The University of Hong Kong. Lubchenco, J. 1978. Plant species diversity in a marine intertidal algal community: importance of food preference and algal competitive 39

J.H. Liu

abilities. American Naturalist 112:23-39. Lubchenco, J. and Cubit, J. 1980. Heteromorphic life-histories of certain marine algae as adaptations to variations in herbivory. Ecology 61 :676-87. Lubchenco, J. and Gaines, S.D. 1981. A unified approach to marine plant-herbivore interactions. I. populations and communities. Annual Review of Ecology 12:405-37. Morton, B. 1982. An introduction to Hong Kong's hydrographic environment with special reference to the north-eastern New Territories. In The Marine Flora and Fauna of Hong Kong and Southern China (ed. B. Morton and C.K. Tseng), 25-53. Proceedings of the First International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1980. Hong Kong: Hong Kong University Press. Nicotri, M.E. 1977. Grazing effects of four marine intertidal herbivores on the microflora. Ecology 58: 1020-32. Quadir, A., Harrison, P.J. and DeWreede, R.E. 1979. The effects of emergence and submergence on the photosynthesis and respiration of marine macrophytes. Phycologia 18:83-8. Slocum, C.J. 1980. Differential susceptibility to grazers in two phases of an intertidal alga: advantages of heteromorphic generations. Journal of Experimental Marine Biology and Ecology 46:99-110. Southward, A.J. 1964. Limpet grazing and the control of vegetation on rocky shores. In Grazing in intertidal and marine environments (ed. D.J. Crisp), 265-73.

40

Oxford: Blackwell. Steneck, R.S. 1982. A limpet-coralline alga association: adaptations and defenses between a selective herbivore and its prey. Ecology 63:507-22. U nderwood, A.J. 1979. The ecology of intertidal gastropods.Advances in Marine Biology 16:111-210. Underwood, A.J. 1980. The effects of grazing by gastropods and physical factors on the upper limits of distribution of intertidal macroalgae. Oecologia 46:201-13. Underwood, A.J. 1981. Structure of a rocky intertidal community in New South Wales: patterns of vertical distribution and seasonal changes. Journal of Experimental Marine Biology and Ecology 51 :57-85. Underwood, A.J. and Jernakoff, P. 1981. Effects of interactions between algae and grazing gastropods on the structure of a low-shore intertidal algal community. Oecologia 48:221-33. Underwood, A.J. and Jernakoff, P. 1984. The effects of tidal height, wave-exposure, seasonality and rock-pools on grazing and the distribution of intertidal macroalgae in New South Wales. Journal of Experimental Marine Biology and Ecology 75: 71-96. Vadas, R. and Elner, R. 1992. Plant-animal interactions in the north-west Atlantic. In Plant-Animal Interactions in the Marine Benthos (ed. D.M. John, S.J. Hawkins and J.H. Price), 33-60. Systematics Association Special Volume No. 46. Oxford: Clarendon Press.

Asian Marine Biology 10 (1993): 41-44

BIOSYNTHETIC CONDITIONS AND PROPERTIES OF STREPTOMYCES SP. CHITINASE ISOLATED FROM THE MANGROVE RHIZOSPHERE Zheng Zhicheng, l Zhou Meiyingl and Zheng Tianling2 IDepartment of Biology, Xiamen University, Xiamen 361005, China 2Environmental Science Research Centre, Xiamen University, Xiamen 361005, China

Abstract The paper reports upon the biosynthetic conditions and some properties of chitinase produced by Streptomyces sp. isolated from the mangrove rhizosphere. The results show that (NH4 )2 SO 4 and organic nitrogen promote the biosynthesis of chitinase, but carbon sources do not. Higher chitinase production was obtained when Streptomyces sp. was grown in media with either 1.5% steeped corn liquor or 2.0% wheat bran. The optimum culture conditions were: pH 7.0 and between 1.0-1.5 mL inoculum at 30°C for 5 to 6 days. The biosynthesis of chitinase was induced by various forms of chitin, e.g., colloidal chitin, demineralized chitin and deacetyl chitin. Hydrolysis of chitin by chitinase occurred over a broad pH range (3.0-8.5). The optimum pH was 5.5, with better stability within a range of pH 4.0 to 7.5. The enzymatic activity increased with temperature within the temperature range of 30°C to 60°C. The optimum temperature was 60°C. Chitinase activity was 90% at 60°C and exhibits higher temperature stability.

Introduction

Materials and methods

Chitin is the principal structural component of insect and crustacean exoskeletons. The human processing of these shellfish generates a waste disposal problem and chitinase is essential to a bioconversion process in which waste shellfish chitin is enzymatically hydrolyzed to Nacetylglucosamine which, in turn, is assimilated by an edible yeast (Carrod and Tom 1978), and can produce ethanol (Cody et al. 1990). Chitinase may be utilized in biological preparations and in the cell fusion of fungi (Sietsma 1981). This paper describes the biosynthetic conditions and some properties of Streptomyces sp. chitinase isolated from samples of the mangrove rhizosphere.

Test strains of Streptomyces sp. were isolated from samples of the mangrove rizosphere (Zheng et al. 1989). The minimal medium was composed of the following mineral salts (%): 0.07 K 2HPO, 0.05 NaCI, 0.05 MgS0 4 ·7H 2 0 and 0.001 FeS0 4 ·7H 2 0 at pH 7.0. The induced medium was composed of minimal medium plus 2.0% demineralized chitin. Fermentation proceeded in a 500 mL flask containing 50 mL medium inoculated with 1.5 mL spore suspension (1.5 x 107 spores·mL- 1), at 30°C, and shake cultured (240 rpm) for 5 days. The culture supernatants were assayed for chitinolytic activity according to the improved method of hexosamine determination of 10hnson (1971). A

Z.C. Zheng, M.Y. Zhou & T.L. Zheng

unit of chitinase activity is defined as the quantity of the enzyme which releases 1 f..lg Nacetylglucosamine (1 mL sample, 5 mg colloidal chitin, 40°C, 1 h).

Results Effect of carbon-nitrogen sources on chitinase biosynthesis

on the biosynthesis of chitinase were examined in the induced medium. The results indicate that biosynthesis of chitinase is affected by culture conditions. The highest chitinase activity was obtained under conditions of pH 7.0, 30°C, an inoculum size of 1.0-1.5 mL and 5 to 6 days (Figs. I and 2).

Some properties of chitinase

TeSts were undertaken in the induced medium whereby different carbon and nitrogen sources were added. The induced medium served as a control. The results show that (NH 4)2 S04 and organic nitrogen promote biosynthesis of chitinase. The highest chitinase activity (284 u'mL- ' ) was obtained in the induced medium to which had been added 1.5% steeped corn liquor. Carbon sources (starch, glucose, sucrose, maltose, fructose, mannitol) did not promote high chitinase activity (Table I).

The addition of various chitins to the minimal medium (Table 2) suggests that chitinase is an induced enzyme. Colloidal chitin, chitin and demineralized chitin are good inducers, especially at concentrations of 2.0% and 3.0% Table 2. Effects of various chitins on chitinase activity (u·mL-1). Conc. (%)

1.5

Inducers

2.0

3.0 -~----.----~

Effect of culture conditions on the biosynthesis of chitinase The effects of initial pH, amount of inoculum, temperature, amount of aeration and culture time

95 78 75 42

Colloidal chitin Chitin Demineralized chitin Deacetyl chitin Control

190 176 115 76

197 180 161 93 0

Table 1. Effects of carbon-nitrogen sources on chitinase biosynthesis (u·mL-1). Inorganic Nitogen

Organic Nitrogen

Carbon

Conc. (%)

Conc. (%)

Conc. (%) Addition

0.3

0.5

(NH 4)2 S04

166

184

NH 4CI

178

NH 4N0 3 (NH 4)2 C0 3

Control

42

0.5

1.5

2.0

Addition

2.0

Steeped corn liquor

205

284

210

Starch

52

162

Yeast extract

175

164

155

Glucose

20

150

143

Pepton

184

180

160

Sucrose

35

28

36

Bean powder

152

187

177

Fructose

43

Wheat bran

163

196

202

Maltose

35

Mannitol

16

Addition

150

Chitinase of Streptomyces

The effects of pH on chitinase activity and the stability of chitin hydrolysis were examined in mixtures of 1 mL enzyme and 1 mL citrate-buffer (0.1 M at various pH values) containing 5 mg

colloidal chitin, incubated at 40°C for 1 h. The hydrolysis of chitin occurred over a pH range of 3.0 to 8.5, with best stability within a pH range of 4.0 to 7.5, and an optimum of pH 5.5 (Fig. 3).

150

150

/ - 7 - ' - ............ '

/

/ :::;-100

~

6 28 1.0

7 30 1.5

8 32 2.0

9 34 2.5

Fig. 1. Effects of initial pH, amount of inoculum and temperature on the biosynthesis of chitinase.

day

.q

~

10 60

-

ee_

I

~ Q::;

I I I

> 60

.~

Q)

.~ 40 ~ Q::;

20 0

3456789 pH

Fig. 3. Effects of pH on chitinase activity and stability. Enzyme activity Enzyme stability

80

.q

I I

>

20

'\

8 50

6 10

Amount of aeration (mL) Time (days)

I I

60

Q)

\

100

80

~ 40

\

Fig. 2. Effects of culture time and amount of aeration on the biosynthesis of chitinase.

100

.j

4 30

2 20

ml

Initial pH Temperature (QC) Amount of inoculum (mL) ........ .

~

I'

I'

-

, , --~' . O....::;;;;..&...----L.--L_&...-.....L.----L._L..-...L..-........---L._

O'--~~~"""&----"'---''--~....I.-~--'---'

5 26 0.5

\, \

,

I'

pH 4 °C 24 ml 0

,

/ i i

Fig. 4

I

30

40

50 °C

60

70

Effects of temperature on chitinase activity and stability. Enzyme activity Enzyme stabiity 43

Z.C. Zheng, M.Y. Zhou & T.L. Zheng

The effects of temperature on chitinase activity and stability of chitin hydrolysis were also examined in mixtures of 1 mL enzyme and 1 mL citrate-buffer (0.1 M, pH 5.0) containing 5 mg of colloidal chitin, incubated at various temperatures for 1 h. The results show that the enzymatic activity of chitin hydrolysis increased with temperature, within a range of 30°C to 60°C. The highest activity occurred at 60°C. Chitinase stability was maintained within a temperature range of 30°C to 60°C and 90% activity was retained at 60°C. The activity declines rapidly at temperatures > 60°C (Fig. 4). A reason for the decline may be deactivation of chitinase at higher temperatures.

Discussion Sources of chitin are abundant in nature. Chitins are structural components of crustaceans, insects, fungi, protozoa and nematodes. Chitin is an unbranched polysaccharide composed primarily of B-l,4 linked N-acetylglucosamine residues with occasional glucosamine residues (Brimacombe and Webber 1964), is highly resistant to organic solvents and requires strong mineral acids for solubilization. Microbial organisms producing chitinase include bacteria (Cody 1989), molds,

yeasts (Cody et al. 1990) and actinomycetes (Hsu and Lockwood 1975). Microbial chitinase is important in the conversion of waste chitin to Nacetylglucosamine which, in turn, is assimilated by other micro-organisms to produce some fermentation products such as edible yeast and ethanol. Microbial chitinase thus has a broad application and could be developed. Marine Streptomyces sp. is able to produce more chitinase (150 u'mL-') in a medium containing chitin used as a sole carbon source, e.g., 2.0% demineralized chitin. The highest chitinase activity (284 u'mL-') was obtained under the specified conditions of 1.5% steeped corn liquor, pH 7.0 at 30°C for 5 days. The enzymatic activity of chitinase has a wide range and a better pH stability. The optimum temperature for enzymatic action and stability of the chitinase is high. The results presented in this paper offer information for the further study, development and application of microbial chitinase.

Acknowledgements The authors wish to thank Prof. Brian Morton and an anonymous referee for their critical reading of the first draft of this paper.

References Brimacombe, J.S. and Webber, J.M. 1964. Mucopolysaccharides: Chemical Structure, Distribution and Isolation, vol. 6, 18-42. New York: Elsevier. Cody, R.M. 1989. Distribution of chitinase and chitobiase in bacillus. Current Microbiology 12:201-5. Cody, R.M., Davis, N.D., Lin, J. and Shaw, D. 1990. Screening microorganisms for chitin hydrolysis and production of ethanol from amino sugars. Biomass 4:285-95. Carrod, P.A. and Tom, R.A. 1978. Bioconversion of shellfish chitin wastes: process conception and selection of microorganisms. Journal of Food Science 43: 1158-61. Hsu, S.C. and Lockwood, J.L. 1975. Powdered 44

chitin agar as a selective medium for enumeration of actinomycetes in water and soil. Applied Microbiology 3:422-6. J ohnson, A.R. 1971. Improved method of hexosamine determination. Analytical Biochemistry 44:628-35. Sietsma, J.H. 1981. Solubility of (I - 7 3)-B-DI (I - 7 6)-B-D-glucan in fungal walls: importance of the presumed linkage between glucan and chitin. The Journal of General Microbiology 125:209. Zheng, Z.C., Zhou, M.Y. and Yao, B.X. 1989. Composition and biological activity of actinomycetes in mangrove rhizosphere. Journal of Xiamen University (Natural Science) 3:306-10.


MARINE ENCLOSURE ECOSYSTEM EXPERIMENTS TO STUDY RED TIDE MECHANISMS AND PROCESSES IN XIAMEN HARBOUR, CHINA * Lin Yu, Zhuang Dongfa, Tang Senming, Chen Xiaolin Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China

Abstract Marine enclosure ecosystem experiments have been conducted in a land-based tank at the Third Institute of Oceanography by the Marine Experimental Enclosure Research Centre (MEERC) to understand red tide stimulating mechanisms. Three experiments on an artificially induced red tide are discussed in this paper. It demonstrates the relationships between the occurrence and scale of red tides and environmental conditions, interspecific reactions and succession. As the results obtained are similar to natural red tide processes observed in western Xi amen Harbour, it is clear that the experiment offers a means of controlling and forecasting red tides in this area.

Introduction The sea is a huge integrated ecosystem of water, sediments and biological components, among which material and energy transference is continuously going on due to water movements. Thus, each specific ecosystem in the sea is maintaining its balance by regular and variable changes. Simultaneous transient water movements make investigation of the sea so much more difficult while ecological results obtained in the laboratory cannot be simply extrapolated to the natural system due to the multidimensional interrelationships of the environment. Marine enclosure ecosystem experiment (MEEE) technology, characterized by its multidisciplinary nature, has been developed over the last three decades. In this controlled enclosure ecosystem, the assessment and study of a marine ecosystem can be conducted in terms of the dynamics of biological succession, energy transference, physical-chemical variations and the timing of biophysiological activities. The system has bridged the gap between flask and sea where difficulties remain in investigation both in the

laboratory and the field (Grice and Reeve 1982; Wu et al. 1988; Lalli 1990). From 1983 to 1986, with the financial aid of The State Oceanographic Administration of China and The International Development Research Centre of Canada, the co-operative Marine enclosure ecosystem experiment by Canada and China has been successfully realized through the efforts of scientists and an international symposium held in Beijing in 1987 to summarise the work. As a result, an experimental base for marine enclosure ecosystem experiments in China was set up by the Marine Experimental Enclosure Research Centre, The State Oceanographic Administration of China. Since 1984, the Marine Experimental Enclosure Research Centre has conducted several experiments in which a total of 51 enclosures were employed to study the effects and fate of pollutants, for example, heavy metals, oil and dispersants (Tang et al. 1990; Zhuang and Lin 1991; Wong and Harrison 1992). Since the spring of 1990, experiments using marine enclosure ecosystem experiment techniques have been conducted to investigate red tides caused by eutrophication.

* This paper was presented at a colloqium on red tides in Hong Kong and South China convened in Hong Kong from 9-11 September 1992.

Y. Lin, D.F. Zhuang, S.M. Tang & X.L. Chen

In these experiments, the interrelationships between some important nutrients, such as N, P, Mn, Fe and B 12' to red tide occurrence and scale, and the general rules of the interactions between the occurrences and species has been studied. Here, the results of three (experiment RI' R2 and R 3 ) out of four experiments are discussed.

Materials and methods The enclosures

Woven polypropylene bags, lined with a layer of polyethylene to prevent water mixing, were used in experiment RI' About 7.5 m 3 of the water column was enclosed in each bag (Fig. lA). The enclosures used in the experiment R2 were fibreglass barrels with volumes of 1.5 m 3 and lined with a layer of polyethylene (Fig. 1B). In addition to the enclosures for the mesocosms experiment, a microcosms experiment, using 60-L polyethylene barrels, was conducted. Facilities and methods

The experiments were carried out in a land-based tank, of 20 x 10 x 5 m 3 , at the Third Institute of Oceanography. The enclosures were fixed to a steel frame and floated in the middle of a larger tank (Fig. lA). The barrels were made to stand in the tank. Before the experiment, nearshore water

was pumped in and distributed simultaneously into the enclosures through a manifold. The big tank was kept at a given depth of water and sea temperature maintained by pumping in fresh seawater every day. This also made up water loss due to tank leakage. The RI experiment was conducted during May and July 1990. Three phases made up the experiment. In the first phase (0-22 days) observations were made to compare variations in phytoplankton biomass under eutrophic and oligotrophic conditions. Bag Cl was set up as the control in which the concentrations of nutrients were monitored with time and compensated for to maintain nutrient levels similar to those in the sea. Bag HI had excess nutrients added and maintained at levels of 30, 20 and 3 JlIllol·L- 1 for nitrate, silicate and phosphate, respectively, by adding nutrients whenever values fell. For bag L I, the concentration of phosphate was maintained low to mimic nutrient levels in the seawater of Western Xiamen Harbour after a spring bloom, while the concentrations of nitrate and phosphate were kept at 15 and 0.2 JlIllol·L-I, respectively. The observations made in the second phase (23-62 days) were to follow phytoplankton dynamics under conditions of high nutrient level and when nutrient levels are transformed from an oligotrophic to a eutrophic state by raising the concentrations of nutrients in bag Cl and LI to the level in bag HI' The addition of nutrients was

-4mt Bag

A Fig. 1.

46

B

The design of the enclosure experiment. A, enclosure bag; 8 , experimental tank and fibreglass barrel.

Red tides in Xiamen Harbour

halted in the third phase (63-76 days) when the released nutrients from the sediments are supposed to support algal growth. The R2 experiment was carried out in the spring of 1991. The nutrients in each barrel were kept at the level of 50 and 3 }JlIlol·L-1 for nitrate and phosphate, respectively. At the same time, concentrations of 0, 25, 50 and 100 Ilg·L-I of soluble manganese were added to barrels C 2, L 2, M2 and H 2, respectively. A microcosm experiment (R3) repeated the R2 experiment in the autumn of 1991. The added water was aged in order to induce algal blooms other than diatoms. Except for C 3 , which was used as a control with no manganese added, all barrels were contaminated with manganese at concentrations above 1.4 mg· L- I. The analytical methods used in the experiments are described by Lin et al. (1992a, b, 1993).

phytoplankton biomass occurred in the phosphate limited bag, L I. However, diatoms bloomed in bag LI when excessive nutrients were added. Dinoflagellates and chrysophytes dominated blooms which were observed in all the bags after 45 days (Fig. 2). In experiment R 2 , the diatom, Skeletonema costatum , formed a bloom four days after the start of the experiment and the numbers of cells reached 3.0, 2.6, 2.7 and 3.0 x 107-L- I in bags C 2, L 2, M2 and H 2, respectively (Fig. 3). During the R3 experiment, an Oscillatoria bloom occurred during which the peak in cell density was 6.1 x 107·L-I, three times that of bag L3 (Fig. 3). The effects of environmental conditions on algal blooms Water column stability. The differences between the enclosed water columns, where the red tide or algal bloom had been induced and the seawater in the vicinity, were that the enclosed water was rather stable compared with the natural water which is always disturbed by tidal currents

Results In experiment RI' an algal bloom was induced in bag HI in the first phase while little change in

50.0

......

CBag

~

LBag

0.--0 H Bag

-

40.0

( 'f) I

E

•

C)

:c E

30.0

as I

0

20.0

10.0

o 4

9

14

21

27

34

41

48

55

62

69

76 (d)

Fig. 2. Changes in chlorophyll-a values in the enclosure bags during the R1 experiment. 47

Y. Lin, D.F. Zhuang, S.M. Tang & X.L. Chen

----

C2 0---0 L2 A-·A M2 A--ll. H2

8

7

-

... '

6

.

...~./

~

./ ./

~ 0

z• z 8

-

0

4

2

12 (d)

9

6

..-.. C3 0--0 L3

C)

0 ...J

7 6

o 1 34

6

8

11

14

17

20

(d)

Days Fig. 3. Changes in algal cell density during the R2 and R3 experiments.

and waves. The area where red tides occur frequently are inside Baozhuyu Bay in western Xiamen Harbour, where the sea is calm and water exchange weak. The similarity of the water conditions here to the enclosed water column may be one important factor influencing red tide occurrences (Zhang et al. 1989; Lin et al. 1992a).

especially active phosphate, in western Xiamen Harbour, have a close relationship with the occurrence and developments of red tides in this area. This is also indicated by the results of a closed observation on red tides in the area in 1986 and 1987 (Chen 1987; Zhang et al. 1989; Lin et al. 1992a).

The relationships between nutrient level and red tide occurrence

The relationship between dissolved manganese and red tides

The three experiments showed that eutrophication of the enclosed water column always led to either algal blooms or red tides, if certain physical factors were met. Investigations in western Xiamen Harbour demonstrated that nutrient levels of the area are in a mesotrophic state. It could be, therefore, that basic conditions for a red tide occurrence in the enclosed water column are met when nutrients are added. In comparison, bag Ll did not bloom in the first phase at low phosphate concentrations. It did, however, when sufficient nutrients were supplied. This shows that the concentrations of nutrients,

Figures 4 and 5 show that, though different concentrations of dissolved manganese were added, variations in phytoplankton numbers and structure were almost the same. This suggests that dissolved manganese at a level of 3-4 Ilg·L-l, as in barrel C 2 , is sufficient for the multiplication of algae and red tide occurrences. The excessive dissolved manganese at levels < 80 Ilg·L-1 in seawater would make no difference to phytoplanktonic biomass and community structure. The situation changed, however, when the concentration reached lA mg·L-l, as in barrel L3 where the structure of the phytoplankton

48


~ 1.3° c:

~

90

"s1.10

"'C Q)

>

O~

70

(/)1

.~-:-I o~

-0

0

8.0

50

-

H2 i 6.0 M2 -:-' L2 .:; 2.0 C2 0.0

30

0

C3

0)

c:

0

t

• L3

10 0

2

4

6

9

12

1 34 6 8

11

14

17

20

Days

Fig. 4. Changes in the concentrations of dissolved manganese in the R2 and R3 experiments.

100

100

80

80

60

60

40

40

(ft.

C2

20

20 0

0 0

2

4

6

9

12

100

100

80

80

60

60

40

40

20

20

0

2

4

0

2

4

6

9

12

6

9

12

(ft.

0

0 0

2

4

6 Days

9

12

Days

Fig. 5. The percentage changes in the importance of phytoplankton groups in the R2 experiment. (0 - diatoms, • - dinoflagellates, ~ - microflagellates, ® -

Cryptophyta).

49

Y. Lin, D.F. Zhuang, S.M. Tang & X.L. Chen 100~-------------------,

100 - - - - - - - - - - -.......

80

80

60

60 40

20

20

o1

3 4 6 8 11 Days

14

17 20

o1

34 6

8 11 Days

14

17 20

Fig. 6. The percentage changes in the importance of phytoplankton groups in the R3 experiment. (€l - microflagellates, @ - Cryptophyta. 0 - Cyanophyta.)

community varied and numerical development was confined to a certain extent, in comparison with C 3 (Lin et al. 1993). Interspecijic reactions and red tides Phytoplankton succession. As sufficient nutrients were kept in bag HI' algae bloomed in the

following sequence: diatoms (dominated by Navicula and Nitzchia), dinoflagellates and Chrysophyta. Figure 7 shows the changes in numbers of dinoflagellates and diatoms. The numerical changes seem to show species exclusion, since no dinoflagellates were observable when diatoms bloomed after 11 to 18 days. Dinoflagellates increased to high numbers

8

~

7

CD 6 0

•

~

5

z C)

0 ...J

\

4

\ \

J

3

\

0-0 0

0- -O-~

4

8

12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 Days

Fig. 7. The temporal distribution of diatoms (e (... - ... ) in bag Hl of the Rl experiment. 50

e), dinoflagellates (0- 0) and microflagellates


with the decline of the diatoms until day 45, when few diatoms were detected. After 55 days, diatoms recovered in numbers and dinoflagellates disappeared again at day 69. It is clear from Table 1, that more centric diatom species occurred in the first 10 days; most species of pennate diatoms occurred from 11 to 23 days, disappeared after 47 days and reappeared later. More dinoflagellate species appeared later in the experiment. In view of either the numbers of diatoms and dinoflagellates or the species diversity of both in each phase of the experiment, algal blooms induced by eutrophication in the enclosed water column first occurred in diatoms and then dinoflagellates and microflagellates (~ 20 Jlm). The species and numbers of dinoflagellates always dominated in the later part of the experiment. This phenomenon was repeated in the R2 and R3 experiments. Davis (1982) has commented on the results of Foodweb I experiment, in which phytoplankton succession was similar to our experiments. In general, such succession may not occur in Xiamen Harbour, but this is not contradictory with the results of our experiments. Our experiments

only showed that phytoplankton succession during a red tide proceeds under a eutrophic state. (Lin etal.1992b) It is interesting that the experimental sequence was rather similar to the process of red tide occurrences in western Xiamen Harbour in 1986. The first unusual bloom was dominated by Dactyliosolen mediterraneus for one week. Ten days later Gymnodinium sp. took this position and formed a larger scale dinoflagellate red tide (Du 1988). It can be considered that experiment RI successfully simulated red tide algal succession, which is induced by nutrient enrichment from the seawater of western Xiamen Harbour. It demonstrated the processes of red tide occurrence. The experiment has its practical significance in that the data obtained can be used to forecast possible red tide occurrences in this area. Grazing pressure. These experiments demonstrated that in many mesocosm experiments, zooplankton populations were variously sensitive to pollutant stress which, in turn, led to alterations in ecosystem structure. In this case, the development of phytoplankton populations was

Table 1. The appearance time of various phytoplankton species in bag H1 of the R1 experiment. Appearence time (days)

Ske/etonema costatum Tha/assiosira subtilis Chaetoceros spp. Rhizosolenia sp. Amphora costata Navicula spp. Nitzschia spp. Pleurosigma sp. Amphora ostrearica Dip/oneis bombus Fragilaria sp. Ceratium sp. Gymnodinium sp. Periodinium sp. Exuviaella sp. Prorocentrum micans Chrysophyta microflagellates

(~

20 Jlm)

1-10

+ + + + + + + +

11-20

21-23

24-47

+ + + + + + +

+ + +

+ + +

+

48-58

+

+ +

69-76

+

+ + +

+ + + + + +

+

+

+

+ + + +

+ +

+ +

+ +

+ + +

59-68

+

+ + 51

Y. lin, D.F. Zhuang, S.M. Tang & X.L. Ch en

closely correlated with the zooplankton community and individual numbers (Parsons et al. 1984; Chen et al. 1988; Tang 1992).

Discussion Though these preliminary results can only demonstrate some mechanisms of red tide occurrence at the community level, to understand the whole mechanism will need much more research. The relationships between such factors as Fe, B 12 and organic matter to red tide occurrence and scale, disturbance to the water column and interference with phytoplankton succession by the rate of supply of nutrients, all need to be investigated. Results and data from these types of experiments are necessary for red tide forecasting and control. As the water columns enclosed were typical of western Xiamen Harbour characterized by mesotrophication, some physical and chemical conditions, such as the concentration of dissolved manganese, have already met the requirement for an algal bloom. It is difficult to obtain a

quantitative relationship between environmental factors and algal biomass. What could be done is to analyse ecological effects resulting from changes in these factors. In conclusion, the experiments are limited by the conditions of the experimental seawater. In addition, the materials and energy exchange between sediments and the water column are important links in the process of red tide occurrence. We are examining the possibility of conducting enclosure experiments that combine the pelagic and benthic ecosystems. It is believed that such a system is indispensable to the study of red tide mechanisms.

Acknowledgements The authors gratefully acknowledge the National Science Foundation of China for funding project No. 9389008. Special thanks are due to Prof. Brian Morton for his critical reading of the first draft of the manuscript of this paper. We also thank an anonymous referee for his corrections and suggestions.

References Chen, X.L., Lin, J.M. and Lalli, C.M. 1988. The effects of heavy metals and sediments on zooplankton in a experimental marine ecosystem. Acta Oceanologica Sinica 4:6301. Chen, Y.W. 1987. Analysis the trophic condition of Xiamen Harbour. Marine Environmental Science 3: 15-9. (In Chinese) Davis C.O. 1982. The importance of understanding phytoplankton life strategies in the design of enclosure experiments. In Marine Mesocosms (ed. G.D. Grice and M.R. Reeve), 323-33. New York: Springer-Ver1ag. Du, Q. 1989. Investigations on red tide in the west area of Xiamen sea. Journal of Jinan University (monograph of study on red tides), 57-67. Grice, G.D. and Reeve, M.R. 1982. Marine Mesocosms. New York: Springer-Verlag.

52

Lalli, C.M. 1990. Enclosed Experimental Marine Ecosystems: A Review and Recommendations. New York: Springer-Verlag. Lin, Y., Chen, X.L., Zhuang, D.F., Tang, S.M. and Lin, R.C. 1992a. Preliminary study on red tide caused by nutrient enrichment in marine enclosed ecosystem. Oceanologia et Limnologia Sinica 3:312-7. Lin, Y., Chen, X.L., Zhuang, D.F., Wu, S.S., Cai, Z.P., Tang, S.M. and Lin, R.C. 1992b. Primary analysis on the phytoplankton community structure of red tide processes in marine enclosed ecosystem. Acta Ecologica Sinica 3:213-8. Lin, Y., Tang, S.M., Chen, X.L. and Zhuang, D.F. 1993. The effects of dissolved Mn on the multiplications of two red tide algae in the enclosure ecosystem. Acta Oceanoiogica Sinica 4:91-8.

Red tides in Xi amen Harbour

Parsons, T.R., Harrison, P.I., Acreman, I.C., Dovey, H.M., Thompson, P.A., Lalli, C.M., Lee, K., Li, G.G. and Chen, X.L. 1984. An experimental marine ecosystem reponse to crude oil and Corexit 9527: part 11biological effects. Marine Environmental Research 13:265-75. Tang, S.M., Chen, X.L. and Zhuang, D.F. 1990. Marine ecosystem enclosure experiment and environment protection. In The Third International Conference of Specialists in Marine Fishery-East China Sea Symposium, 1990, 80-4. Tokyo. Tang, S.M. 1992. The effect of BP-II00X dispersant and dispersed crude oil on the phytoplankton populations in MEE. Acta Oceanologica Sinica 2: 130-4.

Wong, C.S. and Harrison, P.I. 1992. Marine ecosystem enclosed experiments. Proceedings of a Symposium held in Beijing, China. Ottawa: International Development Research Centre. Wu, I.P., Chen X.L., Zhuang D.F. and Wu S.S. 1988. Progress in marine ecosystem enclosure experiments. Advances in Ecology 1:43-50. Zhuang, D.F. and Lin, Y. 1991. The effects of nutrients and heavy metals on the plankton in marine enclosed ecosystems. Acta Oceanologica Sinica 4:637-40. Zhang, S.I., Xu, K.C., Chen, Q.H. and Zeng, Z.W. 1989. Observation of a red tide event in the western harbour, Xiamen. Acta Oceanologica Sinica 3 :464-6.

53


SOME CORAL REEF PONTONIINE SHRIMPS FROM VIETNAM

A.J. Bruce Division of Natural Sciences, Northern Territory Museum, P.O. Box 4646, Darwin 0801, Australia

Abstract Records are provided of 25 species of pontoniine shrimps from the coral reefs of Vietnam. Few carideans have been previously reported from Vietnamese seas and all species, except Anchistus miersi De Man, Coralliocaris graminea and Periclimenes brevicarpalis (Schenkel), are now recorded there for the first time, although most are common and well-known Indo-West Pacific species. Most of the species reported are commensals of corals or bivalve molluscs. Many more species associated with other types of host, or free-living, may be expected to occur in Vietnamese waters. The fauna of Vietnam is compared with those of Hong Kong and Singapore.

Introduction The shrimp fauna of Vietnam has attracted very little scientific attention, and few pontoniine shrimps from that country have been reported in the scientific literature. The only citations located are those of Kemp (1922), who reported the occurrence of Anchistus miersi (De Man), Coralliocaris graminea (Dana), and Periclimenes brevicarpalis (Schenkel), all from Pulo Con Dua (Pulo Condore). The pontoniine faunas of both Singapore and Hong Kong are comparatively well known, having been initiated by the studies of Lanchester (1900) and Stimpson (1860), respectively and augmented considerably in more recent times (John son 1961, 1979; Bruce 1979, 1982, 1990a, 1992). Almost 60 species are known collectively from the three regions, but less than half have been collected from any single locality. Both Hong Kong and Singapore represent restricted sites and habitats that have now been long subjected to intense human interference. Their present faunas may well represent their actual and probably diminishing fauna, but the long coastline of Vietnam may be expected to provide a much great diversity in due course when studied in more detail. The present collection was made by Dr T.A. Britaev and Dr Y.Y. Dgebuadze by snorkel and

SCUBA in 1985-87, supported by the Institute of Evolutionary Animal Morphology and Evolution, Moscow, and Marine Research Institute of Vietnam, Nha Trang, and 1989-90, by the SovietVietnamese Tropical Research Centre, and consists primarily of species from branching coral hosts and bivalve molluscs. The collections were made mainly at Tarn, Tre and Mung Islands, off Nha Trang. The specimens reported upon are deposited in the collections of the Northern Territory Museum, Darwin. A parallel collection has been placed in the collection of the Zoological Collection, Moscow State University. Restricted synonymies only are provided, with fuller details being available in Holthuis (1952). Carapace length (CL) refers to the postorbital carapace length.

Systematic Account

Anchistus australis Bruce Anchistus australis Bruce, 1977: 56-62, figs 7-9. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. 19, 3 rn, 7 March 1990, NTM Cr.008374.

A.J. Bruce

Fig. 1. Map of localities mentioned in text; inset, approximate position of localities in the South China Sea.

Remarks. The female has a rostral dentition of 4/ I, the male has a dention that may be interpreted as 5/0 or 4/1. Host. Tridacna squamosa Lamarck [Mollusca: Tridacnidae] . Distribution. Type locality: Capre Cay, Swain Reefs, Great Barrier Reef. Also known from Indonesia, northern Australia, New Caledonia, Fiji and the Marshall Islands. 56

Anchistus custoides Bruce Anchistus custoides Bruce, 1977: 50-56 figs. 46. Material examined. (i) 1 juv., Tre Island, stn 2, 7 m, 14 February 1987, NTM Cr.008375. Remarks. The single example has a carapace length of 2.5 mm, and lacks both second pereiopods, with a single attached first pereiopod

Pontoniine shrimps from Vietnam

and a detached ambulatory pereiopod. The rostrum has three minute denticles distodorsally and the first pereiopod chela has non-cannulate fingers and palm.

24 December 1988, NTM Cr.008380. (ii) 1 ovig. female, Tarn Island, stn. 12, 6 January 1989, NTM Cr.008381. Remarks. The specimens agree closely with previous descriptions.

Host. Pinna sp., [Mollusca: Pinnidae]. Distribution. Type locality: Gillet Cay, Swain Reefs, Great Barrier Reef. Also known from the Ryukyu Islands, Japan; One Tree and Heron Islands, Capricorn Islands, Great Barrier Reef and Seram Island, Indonesia. Anchistus custos Forsskal Cancer custos Forsskal, 1775: 94. Harpilius inermis Miers, 1884: 291, pI. 32 B. Anchistus inermis - Borradaile, 1898:387. Anchistus custos - Holthuis, 1952: 105-109, figs. 86-89. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. 2, 2 m, 13 February 1987, NTM Cr.008378. (ii) 1 male, 1 ovig. female, Tarn Island, stn. 5, 2 m, 20 February 1987, NTM Cr.008376. (iii) 2 juv., Tre Island, stn. 6, 2-4 m, 25 February 1987, NTM Cr.008377. (iv) 1 male, 1 ovig. female, Tre Island, stn. 13,26 March 1990, NTM Cr.008379. (v) 1 male, 1 ovig. female, idem, NTM Cr.008484. Remarks. The specimens are typical of this wellknown, common and widely-distributed species. Host. All specimens were found in association with Pinna sp. or Pinna bicolor Chemnitz [Mollusca: Pinnidae]. Distribution. Type locality: AI-Luhayyah, Yemen. Otherwise recorded from the Red Sea to Mozambique, Japan to South Australia, east to Palau, Caroline Islands and the Fijian Islands. Anchistus demani Kemp Anchistus demani Kemp, 1922: 256-259,figs. 8689. Material examined. (i) 1 male, Tre Island, stn. 12,

Host. Tridacna maxima Lamarck [Mollusca: Tridacnidae] . Distribution. Type locality: Port Blair, Andaman Islands. Also reported from Kenya, Zanzibar, Madagascar, Comoro Islands, Seychelle Islands, Malaysia, Indonesia, Thailand, Great Barrier Reef and New Caledonia. Anchistus miersi De Man (Fig. 3A) Harpilius miersi De Man, 1888: 274, pI. 17, figs. 6-10. Anchistus miersi - Borradaile, 1898: 387. Material examined. (i) 1 male, I ovig. female, Tre Island, stn. 7, 1.5-2 m, 29 November 1985, NTM Cr.008382. (ii) 2 juv., Tre Island, stn. 12, 24 December 1988, NTM Cr.008383. (iii) 1 male, idem, NTM Cr.008384. (iv) I male, Tre Island, stn. 12, 5 January 1989, NTM Cr.008385. (v) 1 male, 1 ovig female, idem, NTM Cr.008386. (vi) 1 male, 1 ovig. female, idem, NTM Cr.008387. (vii) 1 male, 1 ovig. female, Tre Island, stn. 15, 11 January 1989, NTM Cr.008388. (viii) 1 ovig. female, Tarn Island, stn. 4, 9 February 1989, NTM Cr.008389. (ix) 1 ovig. female, Tarn Island, stn. 4,10 February 1989, NTM Cr.008391. (x) 1 male, idem, NTM Cr.008392. (xi) 1 male, idem, NTM Cr.008393. (xii) 1 male, 1 ovig. female, Rua Island, stn. 1, 16 February 1989, NTM Cr.008394. (xii) 1 male, 1 ovig. female, Mui Nam, Tre Island, 3 m, 28 February 1990, NTM Cr.008395. (xiv), 1 male, 1 ovig. female, Tre Island, stn. 19, 3 m, 7 March 1990, NTM Cr.008411. (xv) 1 ovig. female, Tre Island, stn. 4, 9 March 1990, NTM Cr.008412. (xvi) 1 ovig. female, Cape Hoi, Cam Ranh Bay, 12 March 1990, NTM Cr.008413. (xvii) 1 male, 1 ovig. female, Tre Island, stn. 12, 19 March 1990, NTM Cr.008414. (xviii) 1 male, 1 ovig. female, Tre Island, stn. 20, 3 m, 28 March 1990, NTM Cr.008415.

57

A.J. Bruce

2.0 mm F

F

D 13.0 mm CD

10.5 mm B

I

I

B Fig. 2. Coralliocaris superba (Dana). A, carapace and rostrum, male. B, same, female. Coralliocaris venusta Kemp. C, carapace and rostrum, ovigerous female. D, E, same, juvenile females. Coralliocaris viridis Bruce. F, carapace and rostrum, ovigerous female. Harpiliopsis beaupresii (Audouin). G, anterior carapace and rostrum, male.

Remarks. The specimens agree with the data provided by Kemp (1922) and Holthuis (1952). All specimens show the lateral posterior telson spines (Fig. 3A) in a subdorsal position as illustrated by Holthuis (1952, fig. 45). Kemp does not precisely describe the condition in his material, from the Mergui Archipelago, Pulo Con Dua and Jakarta. The posterior telson spines are identical in specimens from Tridacna maxima and T. squamosa. 58

Host. Specimens were collected from Tridacna maxima Lamarck. (v) (ix) (x) (xvii); T. squamosa, Lamarck (ii) (iii) (iv) (vi) (vii) (viii) (xi) (xii) (xiv) (xv) (xvi) (xviii); and Tridacna sp, (i). [Mollusca: Tridacnidae] . Distribution. Type locality: Elphinstone Island, Mergui Archipelago, Burma. First recorded from Vietnam, at Pulo Con Dau, by Kemp (1922). Also known from Kenya, Zanzibar, Tanganyika,


D

c 1.0 mm

c

0.3 mm AEHKL

G , 1.0 mm

B

,O.S mm, F

0.5 mm DI

Fig. 3. Anchistus miersi (De Man). A, posterior telson spines, ovigerous female. Coralliocaris superba (Dana). B, rostrum, female. C, third maxilliped, male, dorsal. D, same, distal segment of endopod. E, posterior telson spines, female. F, fourth thoracic sternite, female. Coralliocaris venusta Kemp. G, third maxilliped, ovigerous female, dorsal. H, same, distal segment of endopod. Coralliocaris viridis Bruce. I, same. Harpiliopsis beaupresii (Audouin). J, third maxilliped, male, ventral. K, third pereiopod, distal propod and dactyl, lateral. L, same, medial.

59

A.J. Bruce

Madagascar, Comoro, Seychelle, Chagos, Maldive and Andaman Islands, Malaya, Singapore, South China Sea, Philippines, Indonesia, Australia, Papua New Guinea, New Caledonia, Ryukyu, Caroline and Marshall Islands; and Tuvalu. Records of specimens from non-tridacnid bivalve hosts, such as Pteria or Pinna spp. require confirmation. Conchodytes kempi Bruce (Fig. 4) Conchodytes biunguiculatus - Kemp, 1922: 280282, fig. 103. Conchodytes kempi Bruce, 1989: 183-184, fig. 3 b-e.

B

Material examined. (i) male, 1 ovig. female, Tre Island, stn. 13, 26 March 1990. NTM Cr.008416. Remarks. The single pair of specimens are distinctly larger than the following species, (CL male 9.4, ovig. female 11.2 mms), and agree with previous descriptions of specimens reported in the literature from the same host. The ambulatory dactyls have a well developed distal accessory tooth and a compressed basal protuberance with a distinctly acute tooth (Fig. 4B). The lateral posterior telson spines (Fig. 4C and D) are not markedly subdorsal and preterminal as in C. biunguiculatus (Paulson), but could be described as very feebly subdorsal and preterminal. The exopod of the uropod bears a small mobile

0.2 mm B

0.2 mm E

A

0.5 mm

CD 1.0 mm

A

E

Fig. 4. Conchodytes kempi Bruce, ovigerous female. A, paragnaths. B, distal propod and dactyl of ambulatory pereiopod. C, posterior telson spines, female. D, same, male. F, exopod of uropod, posterolateral angle.

60


spinule, but is without a distinct fixed tooth (Fig. 4E).

The specimens differ in a number of minor features from the specimens provisionally referred to this species, found in association with Isognomon in the Philippines (Bruce 1989), particularly in their much larger size, but also in the better development of the basal protuberance of the ambulatory dactyls and in the posterior telson spines. In the present specimens, the submedian spines are separated by a small interval, not arising contiguously, from a rounded posterior margin, not from a small projection of the posterior margin, with the spines shorter than, not exceeding, the intermediate spines. The lateral spines are very robust, about half the length of the intermediate dorsal spines, and, as mentioned above, feebly preterminal and subdorsal in position, rather than marginal. These differences suggest than the specimens from Isognomon may represent a distinct taxon, but the examination of further material from this host is necessary before this can be confirmed. The mouthparts of this species have been described by Holthuis (1952) and HipeauJacquotte (1973), (as c. biunguiculatus), but these authors did not describe the paragnaths. These are well developed, with large, feebly bilobed nonspinulate alae (Fig. 4A). The corpus is elongate with a pair of oval submedian eminences anteriorly, with feebly carinate lateral margins, and the median posterior part broadly cannulate, with setose lateral borders. The morphology of the paragnaths in C. kempi shows some remblance to the condition shown in Pontonia pinnophylax (Otto), in which the median part of the corpus is deeply channelled with sharp, setose lateral margins (Bruce 1991), and further emphasizes the close relationship between Conchodytes and Pontonia. Host. Pinna bicolor Cheminitz [Mollusca: Pinnidae]. Distribution. Type locality: Andaman Islands. Also known from the Red Sea, Kenya, Zanzibar, Madagascar, Seychelle Islands, Indonesia, Taiwan, Marshall Islands, and possibly the Philippines.

Conchodytes meleagrinae Peters Conchodytes meleagrinae Peters, 1852:25. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. ?, 2-4 m, 13 February 1987, NTM Cr.008417. (ii) 1 male, 1 ovig. female, Tre Island, stn. 2, 1.5-4m 13, February 1987, NTM Cr.008418. (iii) 1 male, 1 ovig. female, Tarn Island, stn. 4, 10 February 1989, NTM. Cr.008419. (iv) 1 male, 1 ovig. female, Nam Island, Cam Ranh Bay, 2 m, 13 March 1990, NTM Cr.008420. (v) 1 male, 1 ovig. female, Tre Island, stn. 10, 8 m, 27 March 1990, NTM Cr.008421. (vi) 1 male, 1 female, Tre Island, stn. 10, 6 m, 27 March 1990, NTM Cr.008422. Remarks. The specimens present no special features. In the first pereiopods, the carpus is shorter than the merus. Typical carapace lengths for these specimens are: male, 4.0; female, 5.0 mms. Hosts. (i), (ii), (iii), Pinctada sp.; (iv), Pinctada margaritifera (L.); (v), and (vi), Pinctada nigra Chemnitz [Mollusca: Pteriidae]. Distribution. Type locality: Ibo, Mozambique. Otherwise recorded extensively from the Red Sea to Mozambique, Japan to the Great Barrier Reef, east to Hawaii. Corallicocaris superba (Dana) (Figs. 2AB, 3B-F) Oedipus superbus Dana, 1852:25; 1852a: 575; 1855: pI. 37, figs. 2a-f. Coralliocaris superba - Stimpson, 1860: 38. Kemp, 1922: 272-274, figs. 98-99. Material examined. (i) 1 male, Tarn Island, stn. 3, 1.5-2 m, November 1985, NTM Cr.008423. (ii) 1 male, 1 female, idem, NTM Cr.008424. Remarks. All specimens lack both second pereiopods. The males have a rostral dentition of 412, 211 (Fig. 2A) and the female, 412 (Figs. 2B and 3B), with a distinct ventral carina, and are provisionally attributed to C. superba on account of the stronger rostral dentitions than in C. 61

A.J. Bruce

venusta, and the third maxillipeds not having the distal segment of the endopod longer than the penultimate (Fig. 3C), as in C. graminea. The third maxillipeds (Fig. 3C) also show the distinct setal basket on the distodorsal surface of the penultimate segment of the endopod, full of finely granular material, similar to that reported in C. graminea (Bruce 1976). The endopod is robust, with the ischiomeral and basal segments completely fused, the two distal segments slightly exceeding the length of the combined proximal segment, the penultimate segment about 1.3 times longer than broad, the distal segment (Fig. 3D) of similar length, about 2.5 times longer than wide, with the medial margin distinctly concave and the distal end broadly rounded. The posterior margin of the telson (Fig. 3E) is feebly angulate, without a median process, with the lateral pair of posterior marginal spines subequal to the dorsal spine length, intermediate spines robust, 5.5 times longer than basal width, subequal to posterior margin width, submedian spines 5.0 times longer than wide, densely setulose, and about 0.6 of the submedian spine length. The fourth thoracic sternite (Fig. 3F) shows a low transverse ridge, with a slight median eminence and the fifth sternite shows a larger stout, broadly triangular median process. Host. Both lots of specimens were found in associations with Acropora spp. [Sc1eractinia: Acroporidae] . Distribution. Type locality: Tongatabu. Otherwise widely reported from the Red Sea to Madagascar, Ryukyu Islands to the Great Barrier Reef, east to Tahiti. Coralliocaris venusta Kemp (Figs. 2C-E, 3GH) Coralliocaris venusta Kemp; 1922: 274-276, figs. 100-101.

Kemp's description is good, particularly in regard to the second pereiopods, the spacing of the dorsal rostral teeth is variable (Fig. 2C and D). The inferior orbital angle in the type material appears much less distinctly produced than in the present specimens. One juvenile female also has three small dorsal rostral teeth rather than the more usual two (Fig. 2D). The third maxilliped bears a setal basket (Fig. 3G), but less well marked than in C. superba. The distal segment of the endopod is feebly sinuous medially, distally angulate (Fig. 3H).

Host. Acropora sp. [Sc1eractinia: Acroporidae]. Distributions. Type locality: off Tholyram Paar, Gulf of Manaar. Also known from the Red Sea to Mozambique, Seychelle, Comoro and Maldive Islands, La Reunion, Indonesia, Japan, Marshall and Solomon Islands. Coralliocaris viridis Bruce (Figs. 2F, 31) Coralliocaris viridis Bruce, 1974c: 222-224, fig. 1. Material examined. (i) 1 male, 2 juv., Tre Island, stn. 18, 2 m, 6 March 1990, NTM Cr.008427. (ii) 1 ovig. female, idem, NTM Cr.008428. Remarks. The ovigerous female specimen has a slender, shallow rostrum, (Fig. 2F) with a low dorsal carina and a dentition of 5/2, with small acute teeth, the male, 5/1, ~nd the juveniles 4-5/ 1. The third maxilliped is also generally similar to that of C. superba. The ischiomerus: basis articulation is obsolete dorsally, distinct ventrally, and the distal segment of the endopod (Fig. 31) appears feebly grooved proximally along its concave medial margin, a feature that was not discerned in the previous species. The colour pattern of the Vietnamese specimens is unknown. Host. (i) Acropora sp. [Sc1eractinia: Acroporidae].

Material examined. (i) 2 juv., Tarn Island, stn. 3, 1.5-2 m, November 1985, NTM Cr.008425. (ii) 1 ovig. female, idem, NTM Cr.008426. Remarks. The specimen (ii) is without second pereiopods. Although the general agreement with 62

Distribution. Type locality; Mombasa, Kenya. Also known from Mozambique, Sri Lanka, Maldive Islands, Ryukyu Islands, Indonesia and the Great Barrier Reef.


Harpiliopsis beaupresii (Audouin) (Figs. 2G, 3J-I)

Host. Pociliopora verrucosa (Ellis and Solander) [Scleractinia: Thamnasteriidae].

Palaemon beaupresii Audouin, 1825: 91. Harpilius beaupresii - Heller, 1861: 27. Harpiliopsis beaupresi - Borradaile, 1917: 324, 379, pI. 55, fig. 21.

Distribution. Type locality: Egypt. Common throughout the Indo-West Pacific region from the Red Sea to Mozambique, Ryukyu Islands to Great Barrier Reef, east to Marshall Islands and also Easter Island in the Eastern Pacific region.

Material examined. (i) 1 male, 1 ovig. female, Mung Island, stn. 22, 5-7 m, 23 March 1990, NTM Cr.008429. Remarks. The rostral dentition is: male, 6/3 (Fig. 2G); female, 612. In both, the first dorsal tooth is small and appears articulated. The rostrum is more slender in the male and the distal dorsal tooth is minute. The specimens differ slightly from the condition illustrated in Kemp (1922, p. 229, fig. 67), in which the first dorsal rostral tooth is far in advance of the level of the inferior orbital angle, whereas in the present specimens it is only slightly more anteriorly situated. The coxae of the third maxillipeds are widely separated by a broad, unarmed sternite. The endopod has the two distal segments slender, as in H. depressa, as illustrated by Holthuis (1951, pI. 22f) but the ischiomeral segment is markedly broader, distinctly angulated medially at about 0.25 of its length, where there is a small notch, proximal to which a row of some 15 short medially directed ventral submarginal setae are present. This setal row was not present in the Coralliocaris species examined, and the dorsal setal basket found on the penultimate segment in that genus was not present in the present specimen. Also noted by Holthuis (1951), the dactylus of the ambulatory pereiopod (Fig. 3K) is twisted, giving it a most characteristic appearance, diagnostic for the genus, and the ventral propod is devoid of spines, with numerous finely plumose setae. The dactylus is robust, with a dorso-medial carina and a short stout subconical unguis, with the dorsolateral surface strongly convex. The medial aspect of the corpus (Fig. 3L) is quite flat, densely covered by a pavement of small rounded squames, the ventral margin is lamellate with several short submarginal setae laterally, with a pair of more robust sensory setae distolaterally, which may clump together and produce a biunguicate appearance.

iocaste japonica (Ortmann, 1890) Coralliocaris superba var. japonica Ortmann, 1890: 509. iocaste japonica - Holthuis, 1952: 190-195. fig. 94 (partim). - Patton, 1966:279-280, fig. 3b. Bruce, 1974a: 198-199, fig. 7. Material examined. (i) 2 males, 1 ovig. female, Tre Island, stn. 4, 9 March 1990, NTM Cr.008430. (ii) 1 male, 2 ovig. female, idem, NTM Cr.008431. (iii) 1 male, Mung Island, stn. ?, 21 March 1990, NTM Cr.008432. (iv) 2 juv., Tre Island, stn. 13, 26 March 1990, NTM Cr.008433. (v) 1 male, 2 ovig. female, Tre Island, stn. 20, 5-7 m, 28 March 1990, NTM Cr.008434. (vi) 1 male, 2 ovig. female, Tre Island, stn. 21, 5 m, 29 March 1990, NTM Cr.008435. (vii) 1 ovig. female, Tre Island, stn. 9, 4-5 m, 31 March 1990, NTM Cr.008436. Remarks. The specimens show no significant differences from previous descriptions. Host. All specimens were reported from Acropora spp., except (v), which was found on Pociliopora verrucosa (Ellis and Solander), together with Philarius gerlachei. This species is not normally found in association with Pociliopora corals, and the presence of P. gerlachei, another Acropora asssociate, suggests that a labelling error may have occurred. Distribution. Type locality: Kagoshima, Japan. Also known from East Africa to the Philippines and the Cook Islands, apparently absent from the Red Sea. iocaste lucina (Nobili) Coraliiocaris lucina Nobili, 1901: 5; 1906: 57-58. 63

A.J. Bruce

iocaste lucina - Holthuis, 1952: 190-195, fig. 94 (partim). - Patton, 1966: 278-279, fig. 3a. - Bruce, 1974a: 199, fig. 8. Material examined. (1) 1 spm, unspecified locality, NTM Cr.008437. (ii) 1 male, 3 ovig. female, Tarn Island stn. 3, 1.5-2 m, November 1985, NTM Cr.008438. (iii) 4 spms., idem, NTM Cr.008439. (iv) 3 spms., idem, NTM Cr.008440. (v) 4 spms., idem, NTM Cr.008441. (vi) 1 male, 1 ovig. female, Cape Hoi, Cam Ranh Bay, 1.5 m, 12 March 1990, NTM Cr.008442. (vii) 1 male, 2 ovig. female. Tre Island, stn. 9, 18 March 1990, NTM Cr.008443. (viii) 1 ovig. female, 1 juv., stn. 20, Tre Island, 28 March 1990, NTM Cr.008444. Remarks. The specimens show no differences from previous descriptions. Hosts. All specimens were collected from Acropora spp., except for (vi), which was reported as associated with Pocillopora sp. [Scleractinia: Thamnasteriidae] . Parasites. The ovigerous female from stn. 20 was parasitized by a male-female pair of Hemiphryxus malindiae (Bruce 1974) (Isopoda: Bopyridae), det. I.C. Markham. Distribution. Type locality: Eritrea. Also known extensively throughout the Indian Ocean, and Red Sea, and western and central Pacific Oceans as far east as the Cook Islands and Iohnson Atoll.

abdominal segment (Fig. 6B) is acute. The telson (Fig. 6B) is about 2.0 times longer than wide, lateral margins convergent, straight, with the posterior margin (Fig. 6C) about 0.4 of the anterior width, convex with a small acute median point; anterior dorsal spines about 0.22 of telson length, posterior dorsal spines about 0.1, half the anterior spine length; lateral posterior spines small, subdorsal, 0.25 of intermediate spine length, intermediate spines robust, about 0.2 of telson length, submedian spines well developed, slightly smaller and more slender than intermediate spines, strongly setose medially and laterally. The posterolateral angle of the exopod (Fig. 6D) of the uropod is expanded, with a small acute tooth, the immediately adjacent spine is large, robust and strongly curved medially. The dactyl of the third ambulatory pereiopod has the unguis (Fig. 6A) much as shown in Bruce (l974b, fig. 7d), but the denticles are fewer, more acute and distally inclined.

Host. Sponge, unidentified. Distribution. Type locality: Oman, 19° 22.6'N, 57° 53.0'E, I3.5m. Also known from Djibuti, Kenya, Zanzibar, Tanganyika, Maldive Islands, Japan, Hong Kong, Great Barrier Reef, New Caledonia and Fiji. Periclimenes amymone De Man (Figs. 5A, 6E) Periclimenes amymone De Man, 1902: 829-833, pI. 25, fig. 53.

Periclimenaeus arabicus (Calman) (Fig. 6A-D) Periclimenes (Periclimenaeus) arabicus Calman, 1939: 210, fig. 4. Periclimenaeus arabicus - Holthuis, 1952: 13, 130. - Bruce, I974b: 1563-1568,1581, figs. 3 gf, 4-6, 7 c-h. Material examined. (i) 2 ovig. female, Tre Island, stn. 12, 19 March 1990, NTM Cr.008445. Remarks. The specimens correspond well with the original and subsequent descriptions, with a rostral dentition of 6/0 and 7/l, with acute supraorbital spines. The posteroventral angle of the sixth 64

Material examined. (i) 9 spms, Tarn Island, stn. 3, 1.5-2 m, November 1985, NTM Cr.008446. (ii) 1 male, 1 ovig female. Tre Island, stn. 13, 2 March 1990, NTM Cr.008447. (iii), 1 ovig. female, Tre Island, stn. 19, 7 m, 7 March 1990, NTM Cr.008448. (iv), 1 male, 1 ovig. female, 1 juv., Tre Island, stn. 18, 2-3 m, 7 March 1990, NTM Cr.008449. (v), 2 juv., Tre Island, stn. 4, 9 March 1990, NTM Cr.008450. (vi), 4 juv., Tre Island, stn. 12, 19 March 1990, NTM Cr.008451. (vii), 3 males, 1 ovig. female, Mung Island, stn. 22, 5-7 m, 23 March, 1990, NTM Cr.008452. Remarks. The specimens agree well with previous


2.0 mm F

F

,0.3 mm , G

c

1.5mm D

D

,3.0mm

BC

I

Fig. 5. Periclimenes amymone De Man. A, carapace and rostrum. Periclimenes brevicarpalis (Schenkel). S, carapace and rostrum, male. C, same, ovigerous female. Periclimenes consobrinus (De Man). D, carapace and rostrum, ovigerous female. E, same, tip of rostrum. Periclimenes /utescens (Dana). F, carapace rostrum, male. G, same, ovigerous female. 65

A.J. Bruce

1°.2 mm I OP

10.5

mml

ABHM

G

A

N

10.3 L

0.2 mm EFGN

mml

B

10. 1 mm I

J

J

K Fig. 6.

Periclimenaeus arabicus (Calman), ovigerous female. A, third pereiopod, dactyl, unguis and distal corpus. B, sixth abdominal segment and telson. C, posterior telson spines. D, exopod of uropod, posterolateral angle. Periclimenes amymone (De Man), ovigerous female. E, third pereiopod, distal propod and dactyl. Periclimenenes brevicarpalis (Schenkel). F, third pereiopod, dactyl and distal propod, male. G, same, ovigerous female. Periclimenes consobrinus (De Man), ovigerous

female. H, third pereiopod, propod and dactyl. I, same, distal propod and dactyl, (setae not shown). J, same dactyl. Perclimenes /utescens (Dana), ovigerous female. K, third pereiopod, propod and dactyl. L, same, distal propod and dactyl. Periclimenes spiniferus De Man, ovigerous female. M, paragnaths. N, third pereiopod, distal propod and dactyl. Male. 0, first pleopod, endopod. P, second pleopod, endopod.

66


descriptions. They were found in association with Periclimenes spiniferus and Thor sp. [Hippolytidae). The presence of a single distoventral spine in the third ambulatory pereiopod (Fig. 6E) in this species has been reported in Bruce (1980), in contradiction to the statement in Kemp (1922) that the ambulatory propods lack spines. The numerous long flexible setae on the distal propod are also flattened and with finely biserrate margins. The rostrum (Fig. 5A) in the present material is provided with numerous short densely plumose setate, in front of each dorsal tooth, and medially along the proximal ventral margin but submarginally and bilaterally along the distal portion, a condition apparently unusual in Periclimenes species. In the key to the species of the Periclimenes grandis species group provided in Bruce (1987), the substitution of the following for couplet 10 will facilitate the separation of the two species concerned: 10. Ambulatory pereiopods with propods strongly spinulate ventrally; chelae of second pereiopods tuberculate in males; R.l +6-9/2-3 ........................................... P. elegans (Paulson) Ambulatory pereiopods with at most single distoventral spine; chelae of second pereiopodsds non-tuberculate; R.l +6-9/2-3 ............ , .......... . ........................................... P. amymone De Man Host. Acropora spp; [Scleractinia: Acroporidae], except (vi), from A. gemmifera (Brooks), and (ii) (vii) from Pociilopora verrucosa (Ellis and Solander) [Thamnasteriidae]. Distribution. Type locality: Ternate, Indonesia. Also known from the Nicobar Islands, Singapore, Indonesia, Papua New Guinea, Great Barrier Reef, Solomon Islands and New Caledonia. Periclimenes brevicarpalis (Schenkel) (Figs. 5BC, 6FG) Ancylocaris brevicarpalis Schenkel, 1902: 563, pI. 13, fig. 21. Periclimenes (Ancylocaris) brevicarpalis - Kemp, 1922: 185-191, figs. 40-42, pI. 67. Material examined. (i) { male, 1 ovig. female, stn.

3, Lo Bay, Nha Trang, 26 May 1983, NTM Cr.008453. (ii) 1 male, 1 ovig. female, Cape Hoi, Cam Ranh Bay, 2 m, 12 March 1990, NTM Cr.008454. Remarks. In the larger ovigerous female, the carapace' (Fig. 5C) shows a strongly humped appearance as noted by some previous authors, much more marked than in the male (Fig. 5B). The ambulatory dactyls are minutely biunguiculate in both sexes (Fig. 6 F and G) and the pro pods are sparsely setose and devoid of spines. Periclimenes brevicarpalis has been previously recorded from Pulo Con Dua by Kemp (1922). Host. (i) from coral? (ii) sea anemone. Distribution. Type locality: Ujung Pandang, Sulawesi, Indonesia. Otherwise common and widely distributed from the Red Sea to Mozambique, Japan to the South Great Barrier Reef, east to the Marshall Islands. Periclimenes consobrinus (De Man) (Figs. 5DE, 6H-J) Harpilius consobrinus De Man, 1902: 836-840, pI. 26, fig. 54. Periclimenes consobrinus - Bruce, 1972: 403, 409, 412 (key), fig. 1b. - Holthuis, 1981: 795-796, fig. 3 i-I. Material examined. (i) 1 ovig. female, Tre Island, stn. 10, 27 March 1990, NTM Cr.008455. Remarks. The single example unfortunately lacks both second pereiopods, but in all features, corresponds exactly with previous descriptions in regard to its main diagnostic characters, i.e., the rostrum, third maxillipeds and ambulatory propods and dactyls. The rostral lamina (Fig. 5D) is deep, with a dentition of 1 + 5/4, slightly up-curved, and only slightly exceeds the scaphocerite, but distinctly exceeds the carapace length and there is no trace of a postorbital ridge. The ventral margin of the rostrum bears a single median row of short plumose setae (Fig. SE), as in P. lutescens, without bilateral submarginal rows distally, as in P. amymone. The ambulatory pereiopods also 67

A.J. Bruce

resemble those of P. lutescens, with a compressed, strongly hooked simple dactylus (Fig. 51). The propod (Fig. 5H) is about 7.0 times longer than wide, less robust than in P. lutescens, with about 8-9 transverse rows of setae (Fig. 51) distoventrolaterally, which partly conceal the dactyl, distinctly more numerous than in P. lutescens, and without spines. The colour pattern in life was not recorded, and the specimen was collected together with an ovigerous female of Alpheus lottini Guerin.

Kong. Otherwise recorded from the Red Sea to Zanzibar, Japan to southern Queensland, Australia, east to New Caledonia and Caroline Islands, but many records are in need of confirmation, due to possible confusion with P. venustus Bruce.

Host. Pociliopora verrucosa (Ellis and Solander) [Scleractinia: Thamnasteriidae].

Material examined. (i) 2 juv, Tre Island, stn. 13, 26 March 1990, NTM Cr.008460. (ii) 1 juv. female, Tre Island, stn. 20, 9-12 m, 28 March 1990, NTM Cr.008461. (iii) 1 male, 1 ovig. female, idem, NTM Cr.008462.

Distribution. Type locality: Ternate, Moluccas, Indonesia. Otherwise known only from Kenya, Tanganyika, Comoro Islands, La Reunion, southern Great Barrier Reef, Thailand and the Philippines. Periclimenes holthuisi Bruce Periclimenes holthuisi Bruce, 1969: 258-259; 1982: 244-246, fig. 7. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. 19, 5 m, 7 March 1990, NTM Cr.008457. (ii) 1 male, 1 ovig. female, idem, NTM Cr.008458. (iii) 1 male, 1 ovig. female, idem, NTM Cr.008459. Remarks. The three pairs of specimens, each collected separately, from giant anemones, all agree closely with previous descriptions, including Bruce (1989). The closely related and morphologically very similar Periclimenes venustus has been only recently distinguished from P. holthuisi. It is possible that some of the earlier records of P. holthuisi may, upon reexamination, prove to be specimens of P. venustus. The differences are discussed in Bruce (1990b). Host. Stichodactyla mertensi gigantea Brandt, 1836 (= Stoichactis gigantea Forssk~H, 1775) [Actiniaria: Stichodacty lidae]. Distribution. Type locality: Lung Ha Wan, Hong 68

Periclimenes imperator Bruce Periclimenes imperator Bruce, 1967: 53-62, figs. 23-25.

Remarks. All specimens conform closely to previous descriptions. Host. All specimens were found in association with Stichopus variegatus Semper [Holothuroidea: Stichopidae]. Distribution. Type locality, Chumbe Island, Zanzibar. Also known from the Red Sea to Mozambique, Ryukyu Islands to Great Barrier Reef, east to the Hawaiian Islands. Periclimenes lutescens (Dana) (Figs. 5FG and 6KL) Harpilius lutescens Dana, 1852:25: 1852a: 576; 1855: pI. 37, fig. 4. ?Harpilius lutescens - Kemp, 1922:235-237, figs. 72-73. Periclimenes (Harpilius) lutescens - Holthuis, 1952: 88-91, fig. 35. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. 17, 2 m, 5 March 1990, NTM Cr.008463. (ii) 1 male, 1 ovig female, Tre Island, stn. 18, 2 m, 6 March 1990, NTM Cr.008464. (iii) 1 male, 1 ovig. female, idem, NTM Cr.008465. (iv) 1 male, 1 ovig. female, idem, NTM Cr.008466. (v) 1 male, Tre Island, stn. 19, 7 March 1990, NTM Cr.008467. (vi) 3 juv., Tre Island, stn. 4, 9 March 1990, NTM Cr.008468.


(vii) 1 male, Tre Island, stn. 12, 19 March 1990, NTM Cr.008469. (viii) 1 male, 1 ovig. female, 1 juv., idem, NTM Cr.008470.

Remarks. All specimens agree well with previous descriptions. The rostral dentition of the adult males and females (Fig. 5G) is 712, except one female with 7/3. The rostrum is distinctly shorter than the carapace length, horizontal, and deeper in females than males, with a simple median row of short plumose setae distoventrally. A distinct postorbital ridge is present, as noted by Kemp (1922), which is not apparent in the closely related P. consobrinus. The ambulatory pereipods are stout, the prop od (Fig. 6K) about 5.0 times longer than wide, more robust than in P. consobrinus, with only some 4-5 transverse rows of setae (Fig. 6L) distoventrolaterally, distinctly less conspicuous than in P. consobrinus, and without spines. Specimens (v) were found in association with Periclimenes amymone. Holthuis (1952) noted that the specimens referred to this species by Boone (1935), from Tahiti and Nuku Hiva, showed numerous distinct differences from P. lutescens s. str. Boone's illustration of the ambulatory dactyl alone is sufficiently different from that of P.lutescens to indicate that the specimens cannot belong to Dana's species, so that its occurrence further east than the Samoan Islands is yet to be demonstrated. The correct identity of Boone's material also remains to be established. Host. Specimen (vii) was found in Acropora gemmifera (Brook), all others reported from Acropora sp. [Sc1eractinia: Acroporidae]. Distribution. Type locality: Tongatabu, Cook Islands. Widely distributed from the Red Sea to Madagascar; Amami Islands, Japan, to southern Great Barrier Reef, east to Samoan Islands. Periclimenes soror Nobili Periclimenes soror Nobili, 1904: 232. - Bruce, 1978: 299-306, figs. 1-6. Material examined. (i) 1 male, 1 ovig. female, Tre Island, stn. 12,24 January 1989, NTM Cr.008471.

(ii) 1 ovig. female, Rua Island, stn. 16, 16 February 1989, NTM Cr.008472.

Remarks. The specimens do not differ from previous descriptions. Host. Culcita novaeguineae MUller and Troschel [Asteroidea, Oreasteridae]. Distribution. Type locality: Djibuti. Common and widespread throughout the Indo- West Pacific region, from the Red Sea and East Africa to the Hawaiian Islands, and also recorded in the Eastern Pacific region from Panama (Bruce 1978). Periclimenes spiniferus De Man (Fig. 6M-P) Periclimenes petitthouarsi var. spinifera De Man, 1902: 284. Periclimenes (Falciger) spiniferus - Borradaile, 1917: 324, 369, pI. 52 fig. 1. Pericilimenes (Harpilius) spiniferus - Holthuis, 1952: 76-78, fig. 30. Material examined. (i) 1 male, 3 ovig. female, without locality, NTM Cr.008473. (ii) 4 spms., Tarn Island, stn. 3, 1.5-2 m, November 1985, NTM Cr.008474. (iii) 4 spms, Tre Island, stn. 7, 2 m, 29 November 1985, NTM. Cr.008475. Remarks. Many of the specimens lack pereiopods but all second pereiopods preserved are consistent with those of P. spiniferus, as are all other morphological features. Borradaile (1917) provided one of the first illustrations of the paragnaths of a pontoniine shrimp (pI. 52, 1q), referring to the large bilobed lower lip or metastoma. The paragnaths in an ovigerous female of the present specimens (Fig. 6M) closely resembles Borradaile's figure (pI. 52, 1q). The alae are well developed, with feeble development into lobes, the distal medial margin finely spinulate, the proximal medial margin nonspinulate. The proximal median part is short and broad, with feeble carinae laterally. The ambulatory pereiopods are also as illustrated by Borradaile. The dactyl of the third pereiopod (Fig. 6N) is compressed, with a sharp ventral edge. The unguis is distinct, stout, about 69

A.J. Bruce

2.0 times longer than the basal width, about 0.5 of the corpus length. The corpus has the dorsal margin convex, with a single seta at about 0.66 of its length, the ventral margin is almost straight, and a single sensory seta is present distolaterally, and two distomedially. The propod has a pair of long distoventral spines and several similar ventral spines. The male first and second pleopods have been illustrated by both Borradaile (1917) and Holthuis (1952). In the present specimens, these appendages are similar to the earlier data. The endopod of the first pleopod (Fig. 60) is about 3.75 times longer than the distal width, distal third moderately expanded, without distomedial lobule. The proximal three fourths of the medial border bears a series of spiniform setae of distally decreasing length and size, the first finely plumose, the rest spinulose, with short plumose setae around the rest of the medial and distal half of the lateral margin. The endopod of the second pleopod (Fig. 6P) distinctly exceeds the appendix masculina, which also slightly exceeds the appendix interna. The corpus of the appendix masculina is robust, about 4.0 times longer than wide, with about 25 simple spines distributed over the whole ventral surface, with longer spines distally. The proximal medial margin of the endopod bears plumose setae. Distribution. Type locality: Ternate, Indonesia. Also known from most of the Indo-West Pacific region, east to Tahiti, but absent from Red Sea and north-western Indian Ocean.

Periclimenes sp. Material examined. (i) 1 ?, Tre Island, stn. 7, 2 m, 29 November 1985, NTM Cr.008476. Remarks. The single example belongs to the P. grandis group s. str. (Kemp 1922), but can not be identified as it lacks both second pereiopods. Philarius gerlachei (Nobili) Harpilius gerlachei Nobili, 1905: 160; 1906: 45, pI. 4, fig. 10. Philarius gerlachei. - Holthuis, 1952: 152-153, fig. 69. Material examined. (i) 2 jUv., Tre Island, stn. 12, 19 March 1990, NTM Cr.0084 77. (ii) 1 male, 1 ovig. female, Tre Island, stn. 20, 28 March 1990, NTM Cr.008478. Remarks. The specimens all have a rostral dentition of 411, with no postorbital teeth. Specimens (ii) were in association with iocaste lucina. Host. Acropora sp. [ScIeractinia: Acroporidae]. Distribution. Type locality: Arzana Island, Persian Gulf. Also known from the Red Sea to Geyser Reef, Mocambique Channel; Ryukyu Islands to southern Great Barrier Reef, east to Fijian, Samoan and Marshall Islands.

Table 1. Comparison of the pontoniine shrimp faunas of Hong Kong, Vietnam and Singapore. Species

1. 2. 3. 4. 5. 6.

7. 8. 9. 10. 11. 70

Anapontonia denticauda Anchistus austra/is Anchistus custoides Anchistus custos Anchistus demani Anchistus miersi Chernocaris placunae Conchodytes kempi Conchodytes meleagrinae Conchodytes monodactylus Coralliocaris graminea

Hong Kong

Vietnam

+

+ + + + +

Singapore

+

+ + + +

+

+ + + + +


Table 1 (continued)

Species

12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58.

Coralliocaris superba Coralliocaris venusta Coralliocaris viridis Hamodactylus boschmai Hamopontonia corallicola Harpiliopsis beaupresii Ischnopontonia lophos Jocaste japonica Jocaste lucina Onycocaris oligodentata Onycocaris quadratophthalma Palaemonella pottsi Palaemonella ratumana Periclimenaeus arabicus Periclimeneaeus rastrifer Periclimenaeus tridentatus Periclimenes akiensis Periclimenes amymone Periclimenes brevicarpalis Periclimenes commensalis Periclimenes consobrinus Periclimenes cristimanus Periclimenes demani Periclimenes digitalis Periclimenes diversipes Peric/imenes e/egans Periclimenes grandis Periclimenes holthuisi Peric/imenes hongkongensis Peric/imenes johnsoni Periclimenes imperator Periclimenes indicus Periclimenes kempi Periclimenes /utescens Peric/imenes /anipes Peric/imenes ornatus Periclimenes parvus Peric/imenes perturbans Periclimenes seychel/ensis Periclimenes sinensis Periclimenes sorar Periclimenes spiniferus Periclimenes t%ensis Periclimenoides odontodacty/us Philarius ger/achei Philarius imperialis Pontonides sp.

Hong Kong

Vietnam

Singapore

+ + + + + +

+ +

+ + + + + + +

+ +

+ + +

+ +

+ + + +

+ + + +

+ + + + +

+ + +

+ + + +

+ + + +

+ + + + + +

+ +

+

+ +

+

+ + +

71

A.J. Bruce

Philarius imperialis (Kubo) Harpilius imperialis Kubo, 1940: 1-4, figs. 1-3. Philarius imperialis - Holthuis, 1952: 15. Material examined. (i) male, 1 ovig. female, Tre Island, stn. 4, 9 March 1990, NTM Cr.008479. (ii) 1 male, 1 ovig. female, Tre Island, stn. 20, 5-7 m, 28 March 1990, NTM Cr.008480. Remarks. The specimens are as previously described by previous authors. The males have a rostral dentition of 7-8/1, with 1-2 postorbital teeth~ the females 6-7/1, with 1-2 postorbital teeth. The specimens (i) were associated with Periclimenes amymone and Jocaste lucina, (ii) with Jocaste japonica. Hosts. (i) Acropora sp. (ii) Pociliopora verrucosa (Ellis and Solander). [Scleractinia: Acroporidae, Thamnasteriidae]. Philarius species are not generally found in association with pocilloporid hosts and it is possible that the latter record may be a labelling error. Distribution. Type locality: Bonin Island. Also known from the Red Sea to Tanganyika, La Reunion, Singapore, Indonesia, northern Australia to southern Great Barrier Reef, Coral Sea, Caroline and Marshall Islands.

Discussion Data are presently available on 58 pontoniine shrimp species from Singapore, Vietnam and Hong Kong coastal waters. Only two species, Anchistus custos and Periclimenes brevicarpalis, have so far been found to occur in all three regions. Eight species are found in both Vietnam and Singapore and only four in both Hong Kong and Vietnam. Four species are found in both Hong Kong and Singapore but have not yet been recorded from

Vietnam. This leaves 41 species (70%) that are not shared between the three localities. The Periclimenes sp., from Tre Island, is omitted from the above, as it could probably be either P. grandis or P. elegans. The comparisons above are to some extent artificial. The pontoniine coral shrimp fauna of Singapore has been sampled by Patton and reported in J ohnson (1961, 1979) and provides eight species, of which six are associated with branching corals. The coral-associated pontoniine fauna of Hong Kong consists of only two species, with one, Coralliocaris graminea associated with branching corals, reported by Stimpson (1860), but not collected since in Hong Kong waters, although abundant on most Indo- West pacific reefs. The branching coral fauna of Hong Kong is now so restricted that it has not been sampled recently and its associated crustacean fauna is unknown. The present collection from Vietnam indicates the presence of 11 coral-associated pontoniine shrimps, all living in association with branching hosts (44%). Seven species are associated with bivalve mollusc hosts (28%), two with echinoderms (8%), two with coelenterates (8%), one with a sponge host (4%) and two freeliving species (8%). The Hong Kong fauna also includes a number of trawl-caught species from shallow sublittoral waters, as does the Singapore material, which were not sampled in the Vietnamese collections, but could well occur in Vietnamese waters.

Acknowledgements I am most grateful to Dr T.A. Britaev, of the Institute of Evolutionary Animal Morphology and Ecology, Moscow, for making this collection available to me, and for donating the specimens to the Northern Territory Museum crustacean collection. Dr J.C. Markham kindly identified the bopyrid parasite.

References Audouin, V. 1825. Explication sommaire des planches de Crustaces de l'Egypte et de la

72

Syrie, publiees par Jules-Cesar Savigny, membre de I'Institute: offrant un expose des


caracteres nature lies des genres avec la distinctions des especes. Descriptions de l'EgyPt ou receuil des observations et des recherches qui out ete faites en Egypt pendant l' expedition de I' armee francaise. Histoire naturelle 1(4 ):77-98. Boone, L. 1935. Crustacea and Echinodermata, Scientific Results of the World Cruise of the Yacht 'Alva', William K. Vanderbilt, Commanding. Bulletin of the Vanderbilt Marine Museum 6:1-263, figs. 1-13, pIs. 196. Borradaile, L.A. 1898. A revision of the Pontonidae. Annals and Magazine of Natural History 7(2):376-9l. Borradaile, L.A. 1917. On the Pontoniinae. The Percy Sladen Trust Expedition to the Indian Ocean in 1905, under the leadership of Mr. J. Stanley Gardiner. Transactions of the Linnaean Society of London, Zoology (2):323-96, pIs. 52-7. Bruce, A.J. 1967. Notes on some Indo-Pacific Pontoniinae, Ill-IX. Descriptions of some new genera and species from the western Indian Ocean and South China Sea. Zoologische Verhandelingen, Leiden 87: 1-73, figs. 1-29. Bruce, A.J. 1969. Preliminary descriptions of sixteen new species of the genus Periclimenes Costa, 1844 (Crustacea, Decapoda, N atantia, Pontoniinae). Zoologische Mededelingen, Leiden 43(20):253-78. Bruce, A.J. 1972. A review of information upon the coral hosts of commensal shrimps of the subfamily Pontoniinae, Kingsley, 1878 (Crustacea, Decapoda, Palaemonidae). Proceedings of the Symposium on Corals and Coral Reefs, 1969. Marine Biological Association of India 399-418, figs. 1-2. Bruce, A.J. 1974a. A report on a small collection of pontoniinid shrimps from the Island of Farquhar. Crustaceana 27(2): 189-203, figs 18. Bruce, A.J. 1974b. Observations on some specimens of the genus Periclimenaeus Borradaile (Decapoda Nataritia, Pontoniinae) originally described by G. Nobili. Bulletin du Museum National d'Histoire Naturelle, Paris (3)(258)(Zool.) 180: 1557-83, figs. 1-15.

Bruce, AJ. 1974c. Coralliocaris viridis sp. nov., a preliminary note (Decapoda Natantia, Pontoniinae). Crustaceano 26(2):222-4, fig. 1. Bruce, AJ. 1976. Shrimps and prawns of coral reefs. In The Biology and Geology (~r Coral Reefs (ed. O. Jones and R. Endean), 37-94, figs. 1-21, 1 tab. Academic Press. Bruce, A.J. 1977. Pontoni ine shri mps in the collections of the Australian Museum. Records of the Australian Museum 32(2):3981, figs. 1-16. Bruce, A.J. 1978. Periclimenes soror Nobili, a pontoniinid shrimp new to the American fauna, with observations on its Indo- West Pacific distribution. Tethys 8(4):299-306, figs. 1-6. Bruce, A.J. 1979. Records of some pontoniinid shrimps from the South China Sea. IndoMalayan Zoology 1(2): 215-48. Bruce, A.J. 1980. Some pontoniine shrimps from the Solomon Islands. Micronesica 16(2):2619, figs. 1-2. Bruce, A.J. 1982. The pontoniine shrimp fauna of Hong Kong. In The Marine Flora and Fauna of Hong Kong and Southern China (ed. B. Morton and C.K. Tseng), 223-84. Proceedings of the First International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1980. Hong Kong: Hong Kong University Press. Bruce, A.J. 1987. Redescriptions of two littleknown Indo-West Pacific palaemonid shrimps, Periclimenes calmani Tattersall and P. delagoae Barnard. Journal of Natural History 21:1415-23, figs. 1-9. Bruce, A.J. 1989. A report on some coral reef shrimps from the Philippine Islands. Asian Marine Biology 6: 173-92. Bruce, A.J. 1990a. Additions to the marine shrimp fauna of Hong Kong. In The Marine Flora and Fauna of Hong Kong and Southern China II (ed. B. Morton), 611-48. Proceedings of the Second International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1986. Hong Kong: Hong Kong University Press. 73

A.J. Bruce

Bruce, A.J. 1990b. A new cnidarian-associated palaemonid shrimp from Port Essington, Cobourg Peninsula, Australia. Indo-Malayan Zoology 6(1989): 229-43, figs. 1-8. Bruce, A.J. 1991. Notopontonia platycheles, new genus, new species, (Decapoda: Pontoniinae) from South Australia, with remarks on Pontonia pinnophylax (Otto), the type species of the genus Pontonia Latreille. Journal of Crustacean Biology 11(4):175-90, figs. 1-14. Bruce, A.J. 1992. Additions to the marine carridean fauna of Hong Kong, with a description of a new species of Onycocaris (Crustacea: Decapoda: Palaemonidae) from Tuvalu. In The Marine Flora and Fauna of Hong Kong and Southern China III (ed. B. Morton), 329-43. Proceedings of the Fourth International Marine Biological Workshop: The Marine Flora and Fauna of Hong Kong and Southern China, Hong Kong, 1990. Hong Kong: Hong Kong University Press. Calman, W.T. 1939. Crustacea: Caridea. Scientific Reports of the John Murray Expedition 6: 183-224, figs. 1-8. Dana, J.D. 1852. Conspectus Crustaceorum quae in Orbis Terrarum circumnavigatione, Carolo Wilkes e Classe Reipublicae Foederatae e Duce, lexit et descripsit. Proceedings of the Academy of Natural Sciences of Philadelphia 1852: 10-28. Dana, J .D. 1852a. Crustacea. United States Exploring Expeditions during the years 1838, 1839, 1840, 1841, 1842 under the command of Charles Wilkes, U.S.N. 13: 1-685. Dana, J.D. 1855. Crustacea. United States Exploring Expeditions during the years 1838, 1839, 1840, 1841, 1842 under the command of Charles Wilkes, U.S.N. 13: atlas, 1-27, pIs. 1-96. Forsskal, P. 1775. Description Animalium, Avium, Amphibiorum, Piscium, Insectorum, Vermium quae in Itinere Orientali Observavit. Heinek et Faber, Haunia, pp. 19 + xxxii, 1-164. Heller, C. 1861 Synopsis der in rothen Meere vorkommenden Crustaceen. Verhandlungen der K.K. Zoologischen botanisch Gesellshaft in Wien. 11: 1-32. Hipeau-Jacquotte, R. 1973. Etude des crevettes Pontoniinae (Palaemonidae) associees aux 74

mollusques Pinnidae a Tulear (Madagascar). 3. Morphologie externe et morphologie des pieces buccales. Tethys suppI. 5:95-116, figs. 1-7. Holthuis, L.B. 1951. A general revision of the Palaemonidae (Crustacea Decapoda Natantia) of the Americas. 1. The sub-families Euryrhynchinae and Pontoniinae. Allan Hancock Foundation Publication, Occasional Paper. 11: 1-332, pIs. 1-63. Holthuis, L.B. 1952. The Decapoda of the Siboga Expedition. Part XI. The Palaemonidae collected by the Siboga and Snellius Expeditions with remarks on other species. 11. Subfamily Pontoniinae. Siboga Expedition Monograph. 39a 1o:I-252, figs, 1-110, tab. 1. Holthuis, L.B. 1981. Descriptions of three new species of shrimps (Crustacea: Decapoda: Caridea) from Pacific Islands. Proceedings of the Biological Society of Washington 94(3):787-800, figs. 1-4. Johnson, D.S. 1961. A synopsis of the Decapoda, Caridea and Stenopodidea of Singapore with notes on their distribution and a key to the genera of Caridea occurring in Malayan waters. Bulletin of the National Museum, Singapore 30:44-79, pI. 2. Johnson, D.S. 1979. Prawns of the Malacca Straits and Singapore waters. Journal of the Marine Biological Association of India 18(1): 1-54. Kemp, S. 1922. Notes on Crustacea Decapoda in the Indian Museum. XV. Pontoniinae. Records of the Indian Museum 24: 113-208, figs. 1-105, pIs. 3-9. Kubo, I. 1940. A new shrimp, Harpilius imperialis. Journal of the Imperial Fisheries Institute, Tokyo 34:1-4, figs. 1-3. Lanchester, W.F. 1900. On some malacostracous crustaceans from Malaysia in the collection of the Sarawak Museum. Annals and Magazine of Natural History 6(7):249-65, pI.12. Man, J.G. de. 1888. Report on the podophthalmous Crustacea of the Mergui Archipelago, collected for the Trustees of the Indian Museum, Calcutta, by Dr. John Anderson, F.R.S., Superintendent of the Museum. Journal of the Linnaean Society of London, Zoology 22:1-312, pIs. 1-19. Man, J.G. de. 1902. Die von Herrn Professer


Kiikenthal in Indischen Archipel gesammelten Dekapoden und Stomatopoden. In Ktikenthal, W., Ergebisse einer zooIogischen Forschungsreise in den MoIukken und Borneo. Abandlingen hrsg. von des Senckenbergischen Naturforschenden Gesell-schaft 24:467-929, pIs. 19-27. Miers, E.J. 1884. Crustacea. Report of the Zoological Collections made in the IndoPacific Ocean during the Voyage of H.M.S. "Alert", 1881-2, 178-322,513-75, pIs. 1835, 46-52. Nobili, G. 1901. Decapodi e Stomotopodi Eritrei del Museo Zoologico dell'Universita di Napoli. Annuairi del Museo Zoologico della R. Universita di Napoli, N.S. 1(13): 1-20. NobiIi, 1904. Diagnoses preIiminaires de vingthuit especes nouvelles de Stomatopodes et Decapodes Macroures de la Mer Rouge. Bulletin du Museum National d' Histoire Naturelle, Paris 10:228-38. Nobili, G. 1905. Decapodes nouveaux des cotes d' Arabie et du Golfe Persique. (Diagnoses preliminaires). Bulletin du Museum National d'Histoire Naturelle, Paris 11: 158-64, fig. 1. Nobili, G. 1906. Faune carcinologique de la Mer Rouge. Decapodes et Stomatopodes. Annales des Sciences Naturelles (Zoologie) (9)4: 1347, fig. 1-12, pIs. 1-11. NobiIi, G. 1906a. Crustaces Decapodes et Stomatopodes. Mission J. Bonnier et Ch. Perez (Golfe Persique, 1901). Bulletin

Scientifique de la France et de la Belgique 40:13-159, figs. 1-3, pIs. 2-7. Ortmann, A. 1890. Die Unterordnung Natantia Boas. Die Decapoden-Krebse des Strassburger Museums, met besondere Berticksichtigung der von Herrn Dr Doederlein bei Japan und bei der Liu-Kiu-Inseln gesammelten und z.Z. in Strassburger Museum aufbewahrten Formen. I Theil. Zoologische lahrbiich fiir Systematik, Geographie und Biologie der Thiere 5:437-542, pIs. 36-37. Patton, W.K. 1966. Decapod Crustacea commensaI with Queensland branching corals. Crustaceana 10(3):271-95, figs. 1-3. Peters, W. 1852. Conchodytes, eine neue in Muscheln lebende Gattung von Garneeln. Bericht iiber die zur Bekanntmachung geeigneten Verhandlungen der Kongliche Preussischen Akademie der Wissenschaften zu Berlin. 1852:588-95. Schenkel, E. 1902. Beitrag zur Kenntnis der Dekapodenfauna von Celebes. Verhandlungen des Naturforschenden Gesellscheft in Basel 13:485-585, pIs. 7-13. Stimpson, W. 1860. Prodromus descriptionis animalium evertebratorum quae in Expeditione ad Oceanum Pacificum Septemtrionalem a Republica Federato missa, C. Ringgold et J. Rogers Ducibus, Observavit et descripsit. Proceedings of the Academy of Natural Sciences, Philadelphia 1860:22-48.

75


ASSESSING THE LIMITING FACTORS OF RED TIDE BY BOTTLE BIOASSAY* K.C. Ho1 and I.J. Hodgkiss2 ISchool of Science and Technology, Open Learning Institute of Hong Kong, Mongkok, Kowloon, Hong Kong 2Department of Botany, The University of Hong Kong, Hong Kong

Abstract The bottle bioassay technique recommended by the United States Environmental Protection Agency was applied to assess the factors limiting red tides. A study of four species of dinoflagellates isolated from Tolo Harbour showed that the red tide causative organisms were limited primarily by macro-nutrients and their growth was optimal at an N:P (atomic) ratio from 4-22. Suitable temperature, salinity and light conditions were also important. However, these environmental requirements varied from one species to another. The results of the bottle bioassay agreed with field monitoring data. It is suggested that the bottle bioassay technique provides good indications of the responses of dinoflagellates to environmental variations. A complete picture of a red tide can be produced if water quality data, meteorological data and bioassay results are suitably integrated.

Introduction Subtropical Hong Kong has been seriously affected by red tides (Environmental Protection Department, Hong Kong 1992). Tolo Harbour, a semi-enclosed embayment in the northwestern waters of Hong Kong, is most affected by these occurrences as a consequence as well as a cause of eutrophication (Holmes 1988; Lam and Ho 1989a; Wong 1989). In order to remove the nutrients which support algal blooms, the Hong Kong Government has attempted to control pollution in Tolo Harbour. Unfortunately, the control of algal blooms has been of limited success because information on the ecology and environmental requirements of the individual causative organisms is scarce. This paper examines the possibility of using a bottle bioassay to elucidate the limiting factors of four red tide causative dinoflagellates in Tolo Harbour. The results are compared with monitoring and

meteorological data for evaluation of the method.

a

comprehensive

Materials and methods Bottle test hioassay The Bottle Test Bioassay method recommended by Maestrini (l984a, b) and the United States Environmental Protection Agency (1971, 1974) was employed in the presented studies. Four dinoflagellates, namely Ceratium furca (Ehrenberg) Clap. et Lachmann, Gonyaulax polygramma Stein, Gymnodinium nagasakiense Takayama, and Scrippsiella trochoidea (Stein) Loeblich III were selected for bioassay. The objectives of the bioassay analyses were to determine: (1) the limiting factors, (2) their optimal concentrations and (3) the growth potential of the various red tide causative organisms in Tolo Harbour.

* This paper was presented at a colloqium on red tides in Hong Kong and South China convened in Hong Kong from 9-11 September 1992.

K.C. Ho & I.J. Hodgkiss

Limiting factor test. Modified artificial seawater (Burkholder 1963), to which was added an aliquot of the isolated species, was enriched with particular nutrients at different concentrations. This was done to determine which parameter and which concentration was limiting to the yield and growth rate. Two complementary procedures were conducted for each cultivated species: (a) Adding the nutrients or factors singly each positive response indicated that the nutrient (or factor) in question was in short supply, while a response no greater than the unenriched control indicated that one of the other nutrients or some other factor was limiting, or that some form of synergy was lacking. (b) Counter-checking the results by adding all the nutrients (or factors) except one - provided no inhibitors were apparently present, to see

whether the response was minimal when the omitted factor coincided with that which was limiting in procedure A. If the culture with one or more nutrients (or factors) omitted produced larger maxima than a culture receiving the complete complement, this implied that the samples already contained sufficient or excessive quantities of that element and so the enrichment resulted in a toxic or harmful concentration. The test protocols for the limiting factors analysis are summarized in Table 1. Optimal growth concentration determination. Once the identity of the limiting factors was determined, artificial seawater was differentially enriched with the particular limiting nutrients, sometimes singly and sometimes in combination, to determine which condition(s) produced maximal yields. This technique was also

Table 1. The test protocols for the limiting factor analYSis. Protocols

Strength high medium low

4500 lux ± 100 lux 3800 lux ± 100 lux 3000 lux ± 100 lux

high medium low

27°C ± 2°C 22°C ± 2°C 16°C ± 2°C

Salinity -

high medium low

33%0 ± 1%0 29%0 ± 1%0 16%0 ± 1%0

PH

high medium low

8.7 ± 0.05 8.4 ± 0.05 8.1 ± 0.05

Light

Temperature

Nitrogen (NaN0 3 for Limiting Factor Test and NH 4 CI for Optimal Growth Concentration Determination) Phosphorus (K 2 HP0 4 or Na 2 HP04 ) EDT A (Na 2 EDT A) Iron (FeCI 3 ) Trace Metals H3 B0 3 MnCI 2 -4H 2 0 ZnCI 2 CoCI 2 "6H 2 0 CuCI 2 "2H 20 Na 2 Mo0 4 "2H 2 0 78

4.2 mg - N·L-1 0.186 mg - p·L·1 300 mg·L-1 33.05 mg-Fe·L-1 0.196 mg·L-1

0.416 mg·L-l 0.032 mg·L-1 1.428 mg·L-1

0.0214 mg·L-1 7.26 mg·L-1

Red tide limiting factors

accompanied by analysis of the uptake of the nutrient by the species, hence the nutrient concentrations both before and after the culture procedures were determined by relevant chemical methods (American Public Health Association et al. 1985). Determination of growth potential. Surface water samples (1 m below surface) were collected from Inner Tolo Harbour, Outer Tolo Harbour and in the Tolo Channel leading to open oceanic waters once a month from January 1988 to March 1989. The seawater was filtered with 0.45 }...lIIl pore size membrane filters to exclude bacterial and algal contamination. Thereafter, 10 mL of the purified cultivated species (in the vegetative stage and not more than three generations after isolation by observation) was added to 100 mL of the seawater contained in a conical flask. All cultures were cultivated in an incubator with temperature and light control for final yield determination. By comparing the variations in growth during different months in water from different locations, the growth potential of that species in specific locations could be elucidated.

Chambers. Results of cultivation were tested statistically for variance and standard deviations and insignificant (P > 0.05) data were discarded. For the convenience of presentation, data in figures and tables are generally the means of triplicate samples.

Test dinoflagellates

Comparison with monitoring data

The test dinoflagellates were isolated during blooms of the organisms. They were collected by phytoplankton net hauls and were isolated by micro-pipette under an inverted microscope before enrichment so as to avoid the bias of culturing the fastest growing genotypes (Brand 1985). These cultures were maintained in F-2 (minus silicates) medium (Guillard and Keller 1984) in cell wells. Taxonomic identification followed the staining methods recommended by Dodge (1981), Throndsen (1983) and Fukuyo et al. (1990). The algal culture were incubated in a New Brunswick R27 incubator with a temperature precision of ± 0.5°C. The illumination manifolds were fixed inside the incubator and controlled by a computer operated programmer. The light/dark cycle and intensity of the incubation were thus regulated, but frequent calibration and monitoring by a portable irradiance meter was also carried out. The phytoplankton was fixed using Lugol's Iodine solution and cell counts were made under an inverted microscope using Sedgwick Rafter

The bioassay results in the present studies were compared with water quality and climatic data. The water quality data were the biweekly monitoring results collected by the Hong Kong Environmental Protection Department (Environmental Protection Department, Hong Kong 1989, 1990). Some field surveys were also conducted to supplement the information on phytoplankton succession. The climatic data were obtained from the Hong Kong Royal Observatory (1990). Some of the climatic data were reanalysed and compared with the normals in 50 years.

Data analysis The maximum yield was taken from the mean algal concentration measured at the equilibrium phase of growth. The growth rate (J..l) was estimated from cell counts in the exponential phase using the formula of Guillard (1975):

J..l=----.

where Co and Cl indicate the cell member at times To and T I , respectively.

Results Environmental requirements of Ceratium furca

The limiting factors examined for Ceratiuf!l furca were, in order of decreasing significance, high temperature (25-29°C), nitrogen, phosphorus and strong light illumination (Fig. 1). A water temperature of 25-28°C supported the highest 79


Final Algal Yield (cells.mL

o

-....,...., .... I

ASW EDTAandTM Vitamins Nitrogen Phosphorus High Temperature

Low Temperature High Ught Intensity

Low Ught Intensity Nitrogen

+ Phorphorus

Nitrogen

+ High Temperature

Nitrogen

+ Low Temperature

Nitrogen

+ High Ught Intensity

Nitrogen

+ Low Ught Intensity

Phosphorus

+ High Temperature

Phosphorus

+ Low Temperature

Phosphorus


Phosphorus


High Temperature


High Temperature


Nitrogen

I

300

I

I

I

I

I

I

t

)

1,500

1,200

900

600 I

1

I

I

I

Spiking Tests

I

I

I

+ Phosphorus + High Temperature

NItrogen + Phosphorus + Low Temperature ~~-----~---~-.-"

Nitrogen

+ Phosphorus + High Ught Intensity

Nitrogen

+ Phosphorus + Low Ught Intensity All Nutrients

+ High Temperature

+ High Temperature + High Ught Intensity

All Nutrients

t Confirmation Test All Nutrients - High Temperature

I

All Nutrients - Nitrogen All Nutrients - Phosphorus All Nutrients - High Ught Intensity

Fig. 1. Test of limiting factors for Ceratium 'urea on the basis of spiking analyses.

80


0.20

~ J: ZI

!.J

t

0.15

I z

0.10

15

30

25

20

Temperature ("Cl

Fig. 2. The maximum yields of Ceratium furea in different combination of nitrogen supply and temperature.

Table 2. Records of red tide caused by Ceratium 'urea in Tolo Harbour from 1983-89, and the variations in environmental parameters during the days of red tide. Date of red tide

Place

20.8.83

Inner Tolo

1850

28.9

0.063

0.009

14.0

18.4.86

Inner Tolo

250

24.0

0.063

0.004

11.2

4.2.88

Inner Tolo

367

20.1

0.035

0.005

6.1

6-8.6.88

Tolo Channel

1210

29.2

0.022

0.014

20.8

14-20.6.88

Inner Tolo and Channel

10860

29.6

0.015

0.005

24.7

6-7.7.88

Inner Tolo

120

30.4

0.017

0.004

22.5

12.10.88

Inner Tolo

380

27.4

0.021

0.005

18.6

27.1

0.034

0.007

Mean

Max. cell concentration (Cells.mL -1)

Mean water temperature QC

Mean soluble inorganic N (mg-N·L-1)

Mean Mean global incident soluble inorganic radiation P (mg-P·L-1) (MJ·mm-2 )

16.8 (50 years normal = 15.01) 81


yields, and this optimal temperature, when combined with a supply of nitrogenous matter (in the form of ammonium chloride), generated the maximum growth yield (Fig. 2). There was no major difference in the growth potential of this species in Inner Tolo Harbour compared with Outer Tolo Channel and Tolo Channel, suggesting that a highly eutrophicated environment (as in inner Tolo Harbour) is not sufficient to initiate a bloom or red tide of this species. According to the water quality and meteorological data, most red tides of this species occurred in periods of high water temperatures (> 29°C), prolonged sunshine (11-24 MJ·mm- l ) and low nutrient availability (Table 2). This agrees indirectly with the bioassay results in that temperature and light are playing a higher importance in controlling the blooms of Ceratium furca. Environmental requirements of Gonyaulax polygramma Gonyaulax polygramma was shown to be primarily limited by nutrients, particularly nitrogen and phosphorus (Fig. 3). According to the optimal concentration analyses, maximum yield is at an ambient N:P (atomic) ratio of 4-8 when both Nand P are supplied in abundance (Fig. 4). It is shown, however, when the ambient ammoniacal nitrogen concentration is higher than 0.15 mgN·L- I, growth is inhibited but below this critical concentration, yields are generally encouraged by ammoniacal nitrogen (Fig. 5). Variations in salinity did not affect the final yield of the species, but the initial growth was stimulated to a faster growth rate at 28-30%0 (Fig. 6). According to field records, most red tides of G. polygramma occurred at salinity of 29-31 %0 (Fig. 7), and according to the results of Lam and Yip (1990), bloom collapse of G. polygramma was associated with ammonium formation resulting from cell disintegration. These results agree with the bioassay results. Environmental requirements of Gymnodinium nagasakiense Gymnodinium nagasakiense was shown to be co82

limited by phosphorus and nitrogen (Fig. 8). Its yield was maximized at P-concentrations > 0.05 mg·L- I and a total N-concentration > 0.3 mg·VI (Fig. 9). The optimal N:P (atomic) ratio for growth ranged from 11-16. It was also shown that the species tolerated a wide range of water temperature from 19-28°C, and a salinity of 31 %0 was optimal (Fig. 10). According to the growth potential test, Gymnodinium nagasakiense had a good growth potential in eutrophic Inner Tolo Harbour, particularly from late autumn to early winter (Fig. 11). This coincides with the results by Lam and Ho (1989a, b) that blooms of this species peak during October to December each year. Environmental requirements of Scrippsiella trochoidea Scrippsiella trochoidea had its optimal growth in high temperature (> 25°C) and high light intensity (> 4500 lux) (Fig. 12). Phosphorus, however, was found to be the principal limiting factor, although enrichment with EDT A and iron also increased yields. This species had its greatest growth potential in Inner Tolo Harbour during spring to early summer (Fig. 13). During this period, phosphorus and trace metals which are accumulated in the sediment were usually replenished into the surface layers due to mixing (Environmental Protection Department, Hong Kong 1989; Lam and Ho 1989b). It thus seems that these growth limiting factors, as suggested by the bioassay experiments, are closely associated with the occurrence of Scrippsielia trochoidea red tides in the already polluted Tolo Harbour (Lam and Ho 1989a, b).

Discussion Some researchers (Eppley and Dyer 1965; Howell et al. 1967; Hare and Schmidt 1968; Ukeles 1975) have suggested the use of continuous culture techniques in algal assay. However, this method appears to favour small flagellates and diatoms, but dinoflagellates do not grow well in a relatively turbulent condition in the laboratory. Some


Final Algal Yield ( cells.mC

o

300

600

900

1

1,200

)

1,500

ASW

N P

~

EDTA+ Trace Metals

.9 ~

LL

Vitamins

C»

c:

;I

·e

::J

N+P N+EDTA+ Trace Metals N+Vitamins P+EDTA+ Trace Metals P+Vitamins All

Confirmation Tests AII-N AII-P AII-EDTA-Trace Metal All-Vitamins

Fig. 3. The growth responses of Gonyaulax polygramma to various additions of spikes.

83


....-. !..J

5,000

E J!l

B

4,000

1.5

4

8

12

16

20

24

28

32

36

40

N : P (atomic) Ratio Fig. 4. The yields of Gonyaulax polygramma at various N:P ratios. 3,500 . . . . . . . . . - - - - - - - - - - - - - - - - - - - - - - ,

3,000

-E

'i

..J

2,500

en

1i5

0

2,000

"U

1i5

>=

ca « caC u:

1,500

0)

1,000

500

o

+-+-+-+-+-+-~~~~~~~~-+_+-+_+~_r~~

0.03 0.05 0.08 0.10 0.13 0.15 0.17 0.19 0.21

0.23 0.25 0.27

Concentration of NH4CI Fig. 5. Inhibitive effects of ammoniacal nitrogen upon Gonyaulax polygramma growth.

84

Red tide limiting factors 2,500 . , . - - - - - - - - - - - - - - - - - - - - - - - ,

2,000

-

"!..J

E

.!d Q)

1,500

0

"0

Q)

>=

ca

C)

«

1,000

500

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16 17

Day Fig. 6. Effects of salinity change on the growth of Gonyaulax polygramma. 6

o Salinity {o/cx} Fig. 7. Red tides caused by Gonyaulax polygramma in 1983-88, and their frequency distribution in relation to salinity. 85


Final Algal Yield ( cells.m[' )

o I

ASW

1,000

500

I

I

I

1,500 I

2,500

2,000 I

I

~

Spiking Test

1

I

N P

1

EDTA+ Trace Metals Vitamins N+P + EDTA + Trace Metals N+Vitamins P + EDTA+ Trace Metals

[!

P+Vitamins Low Light

11

High Light

I

N+Low Light

N+ High Light P+Low Light

'1

P+ High Light

1

All

J

Confirmation Test

AII-N A11-P

I

'I

AII-EDTA-Trace Metals All-Vitamins - - - - . - -...----------.. ---.

-----~.11

All-High Light Fig. 8. Limiting factor determination for Gymnodinium nagasakiense by means of bottle bioassay.

86


1

Phosphate Concentration ( mg-P.L: 0.01

0.03

0.05

0.07

0.09

0.11

)

0.13

0.15

2,00o+---t--..f-~I----+--+---+--+---I--+--t---+--t---+--;

1,

, ,,

~

,J----- --t---~--N~-N

",

1,00

':;" (ij Cl

«

500

.

o 0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

Nitrogen Concentration ( mg-N.L"' ) Fig. 9. Effects of ammoniacal nitrogen, nitrate nitrogen and phosphates on the growth of Gymnodinium nagasakiense.

87


Salinity %0 25

26

27

28

30

29

31

32

33

1, Temperature

1 l ---y-' ____ --+-----+------1------I ---

, ,,

,,

-Salinity

500

o 15

16

17

18

19

20

21

22

23

24

25

26

27

28

Water TemperatureOC Fig. 10.

88

Effects of water temperature and salinity on the growth of Gymnodinium nagasakiense.


1,500 - - r - - - - - - - - - - - - - - - - - - - ,

, ,"

,

~.,...

\

"

\

'~~·~·~·Outer TOIO\

,,

.,.

I

, ' ,

... e;', .....

I

~

'""'

• • • • • • • • • • •• GJIJt ..... ••••

,.,.

1lt.

,

x~"""

,

\

.~

".'.\ ,,

....

. ................. ~---x' :

o JFMAMJJ

88

ASONDJFM

89

Fig. 11. Variations of growth potential for Gymnodinium nagasakiense in Tolo Harbour (January 1988 to March 1989).

researchers have also suggested carrying out algal assay in closed containers in situ. This, however, causes problems in controlling the environmental factors. The Bottle Test Bioassay method can indicate the environmental requirements of organisms in a relatively controlled and stable environment. Since the results of bioassay closely agreed with in situ water quality and climatic conditions, this method may be particularly useful in determining not only the identity of the primary limiting factors of dinoflagellates, but also the optimal growth concentration. Although the bottle bioassay has these

advantages, it also has one major weakness: The artificial environment of cultivation may not reflect the real situation in the natural environment (e.g., interactions between dinoflagellates, bacteria, and grazers; rapid changes in environmental conditions; neglect of certain important environmental factors) and thus, both bioassay and monitoring data should be examined. This method has been applied widely to freshwater algae but less extensively in the marine environment. Furthermore, marine studies have concentrated on the diatoms (Maestrini et al. 1984a). In order to gain a better understanding of the mechanisms of red tide formation, the present 89


Final Algal Yield ( cells.mL

o ASW

500

1,000

1 )

2,000

1,500

Spiking Test

N P EDTA+ Trace Metals Vitamins High Light Low Light High Temperature Low Temperature N+P N + P + EDTA + Trace Metals N+P+Vitamins N+P+EDTA+ Trace Metal +Vitamins Confirmation Test

AII-N

A11-P All-High Light All-High Temperature AII-EDTA-Trace Metal All-Vitamins Fig. 12.

90

Limiting factor tests for Scrippsiella trochoidea.

2,500

Red tide limiting factors 2,500

~------------------------,

Inner Tolo Harbour

.:p ..... ~.: 2,000

/8

~

6

E

~ 1,500

: .. /

(j)

\

\

0 .:.:.:0

tU

-

~

c::

0

Q..

.t:

'i

1,000

D.

e Cl

t.{

Tolo Channel ;:;J ... , Cl,·, ' ....~,

Q)

,

o

....~

I I I

I

,;...

t;1

I I

. . .. ,0

,, ,

Outer Tolo Harbour ...

I

b

,

500

o

~+---~-4--~--~--+---~~---+--~--+---r-~---+~

Jan Feb Mar Apr May Jun

~

Jul

Aug Sap Oct Nov Dec Jan Feb

MOMh

~

Fig. 13. Growth potential of Scrippsiella trochoidea in various Tolo Harbour waters during the period January 1988-February 1989.

study has been concentrated on the dinoflagellates. Since it is difficult to maintain the quality of filtered seawater and since the collection of 'pure' seawater is particularly difficult in Hong Kong because of the levels of pollution in its coastal waters, freshly prepared artificial seawater was used. Table 3 summarizes the limiting factors for the four red tide causative dinoflagellates studied. For Gonyaulax polygramma and Scrippsiella

trochoidea, phosphorus was the principal limiting factor. Moreover, three out of the four dinoflagellates studied were favoured by a N:P atomic ratio of 4-16, particularly when they were cultivated in a nutrient abundant environment. This optimal N:P (atomic) ratio for the dinoflagellates indicates a slightly nitrogen deficient condition in relation to Redfield's (1958) ratio of 16: I for the oceanic environment. This ratio was also smaller sometimes than the assimilating N:P ratio for phytoplankton (10: 1) 91


Table 3. A summary of limiting factors and optimal environmental conditions for the dinoflagellates studied.

Species

Principal limiting factor(s)

Optimal N:P Optimal Optimal (atomic ratio) illumination temperature O(C) (lux)

Optimal salinity (%0)

Ceratium furea

N

12-22

> 4500

> 25

NOE

Gonyaulax polygramma

P

4-8

< 4500

NOE

NOE

N&P

11-16

> 4500

NOE

> 29

P

6-13

> 4500

> 25

NOE

Gymnodinium nagasakiense Serippsiella troehoidea

NOE = no obvious effect proposed by Ryther and Dunstan (1971). The present results suggest therefore, that the increase of phosphorus supply and the consequent decrease in N:P ratio played a prominent role in controlling the blooms of these dinoflagellates. While nutrients (particularly phosphorus) are of major importance, salinity and irradiance are also important, although their requirements vary from one species to another. As observed in the bioassay experiments, salinity affected the dinoflagellates by reducing the period of the lag phase, Imtlatmg exponential growth and increasing the growth rate of the organisms. However, salinity did not increase the final yields of most organisms, except in the case of Gymnodinium nagasakiense which showed about a 35% increase in yield. This suggests that the effects of salinity on dinoflagellates are very nutrient dependent. The present investigation also showed that there was a higher potential for red tide occurrence

in inner Tolo Harbour than in Tolo Channel than in outer Tolo Harbour. This coincided with the red tide frequency recorded by Chan and Hodgkiss (1987) and Lam and Ho (1989b). On the basis of the bioassay results, red tides in Tolo Harbour are caused by a combination of nutrients and climatic factors acting on the natural marine ecosystem. For the effective management of red tides, therefore, minimizing the input of nutrients, particularly phosphorus, in the form of controlling sewage and industrial waste is essential.

Acknowledgements Thanks go to Mr 10e K.L. Chan for help in preparing the manuscript. This paper is dedicated to the late Dr Catherine W. Y. Lam, who contributed significantly to red tide research in Hong Kong and who advised the authors concerning the algal experiments.

References American Public Health Association. American Water Works Association and Water Pollution Control Federation 1985 Standard Methods for the Examination of Water and Wastewater. 15th ed. Published by the American Public Health Association. Burkholder, P. 1963. Some nutritional relationships among microbes of the sea sediments and water. In Symposium on Marine 92

Microbiology (ed. C.H. Oppenheimer), 13550. Thomas Springfield. Brand, L.E. 1985. Workshop: Culturing. In Toxic Dinoflagellates. Proceedings of the Third International Conference on Toxic Dinoflagellates (ed. D.M. Anderson, A.W. White and D.C. Baden), 538-9. EIsevier. Chan, B.S.S. and Hodgkiss, 1.1. 1987. Phytoplankton productivity in Tolo Harbour,


Asian Marine Biology 4:79-90. Dodge, J.D. 1981. Marine Dinoflagellates of the British Isles. London: HMSO. Environmental Protection Department, Hong Kong 1989. Marine Water Quality in Hong Kong. Environmental Protection Department Technical Report No. EP/.TR3/88. Hong Kong: Government Printer. Environmental Protection Department, Hong Kong 1990. Marine Water Quality in Hong Kong. Environmental Protection Department Technical Report No. EP/TR3/90. Hong Kong: Government Printer. Environmental Protection Department, Hong Kong 1992. Hong Kong Environment-A Review of 1991. Hong Kong: Government Printer. Eppley, R.W. and Dyer, D.L. 1965. Prediction of production in light-limited continuous cultures of algae. Applied Microbiology 13:833-7. Fukuyo, Y., Takano, H., Chihara, M. and Matsuoka, K. 1990. Red Tide Organisms in Japan. Uchida Rokakuho. Guillard, R.P.L. 1975. Division rates. In Chapter IV: Growth Measurement. Handbook of Phycological Methods - Culture Methods and Growth Measurements (ed. J.R. Stein), 289-312. Cambridge: Cambridge University Press. Guillard, R. and Keller, M. D. 1984 Culturing of dinoflagellates. In Dinoflagellates (ed. D.L. Sprctor), 391-443. Academic Press Inc. Hare, T.A. and Schmidt, R.R. 1968. Continuousdilution method for the mass culture of synchronized cells. Applied Microbiology 16:496-9. Ho, K.C. and Hodgkiss, I.J. 1991. Subtropical red tide: an overview of its occurrence. Asian Marine Biology 8:5-23. Holmes, P.R. 1988. Tolo Harbour - the case for integrated water quality management in a coastal environment. Journal of the Institute of Water and Environmental Management 2:171-9. Hong Kong Royal Observatory 1990. Summary of Monthly Statistics of Weather. Hong Kong: Hong Kong Royal Observatory. Howell, J.A.; Tsuchiya, H.M. and Fredrickson,

A.G. 1967. Continuous synchronous culture of photosynthetic microorganisms. Nature 214:582-4. Lam, C.W.Y. and Ho, K.C. 1989a. Red tides in Tolo Harbour, Hong Kong. In Red Tides Biology, Environmental Science and Toxicology (ed. T. Okaichi, D.M. Anderson and T. Nemoto), 49-52. Elsevier. Lam, C.W.Y. and Ho, K.C. 1989b. Phytoplankton characteristics of Tolo Harbour. Asian Marine Biology 6:5-18. Lam, C.W.Y. and Yip, S.S.Y. 1990. A threemonth red tide event in Hong Kong. In Toxic Marine Phytoplankton (ed. E. Graneli, B. Sundstrom, L. Edler and D.M. Anderson), 481-6. Elsevier. Maestrini, S.Y. 1984a. Phytoplankton as indicators of sea water quality: bioassay approaches and protocols. In Algae as Ecological Indicators (ed. L.E. Shubert), 71132. Academic Press Inc. Maestrini, S.Y. 1984b. Test algae as indicators of sea water quality: prospects. In Algae as Ecological Indicators (ed. L.E. Shubert), 13388. Academic Press Inc. Redfield, A.C. 1958. The biological control of chemical factors in the environment. Scienific Americian 46:205-21. Ryther, J.H. and Dunstan, W.M. 1971. Nitrogen, phosphorus and eutrophication in the coastal marine environment. Science 171: 1008-13. Throndsen, J. 1983. Ultra and Nanoplankton Flagellates from Coastal Waters of Southern Honshu and Kyushu, Japan (including some results from the western part of the Kuroshio off Honshu). Research Department of Fisheries Agency , Japan. United States Environmental Protection Agency. 1971. Algal Assay Procedures: Bottle Test. Corvallis: National Environmental Research Center. United States Environmental Protection Agency. 1974. Marine Algal Assay Procedure: Bottle Test. Corvallis: National Environmental Research Center. Unkeles, R. 1975. Continuous culture - a method for the production of unicellular algal foods. In Handbook of Phycological Methods: Culture Methods and Growth Measurement, 93


233-54. Cambridge: Cambridge University Press. Wong, P.S. 1989. The occurrence and distribution of red tides in Hong Kong - applications in

94

red tide management. In Red Tides Biology, Environmental Science, and Toxicology (ed. T. Okaichi, D.M. Anderson and T. Nemoto), 125-8. Elsevier.


EFFECT OF EXPERIMENTAL HARVESTING ON KELP REGROWTH AND ON THE STRUCTURE OF THE SHALLOW-WATER COMMUNITIES OF BERING ISLAND (COMMANDER ISLANDS) V. V. Oshurkov and E.A. I vanjushina Kamchatka Institute of Ecology, Far East Science Centre, Russian Academy of Sciences, PetropavlovskKamchatsky 683000, Russia

Abstract The influence of harvesting on kelp regrowth and on the structure of kelp communities was investigated from May 1989 until July 1991 at five experimental plots in the intertidal and upper subtidal zone of Bering Island (Commander Islands). The abundance of the major kelp species (Laminaria bongardiana and L. dentigera) returned to former levels 2 to 3 years after harvesting, depending on the intensity of harvesting. At the most wave-exposed plot, where L. dentigera initially predominated, a short-term partial replacement of this species by L. bongardiana was observed. Removal of kelp in the upper subtidal zone resulted in increased kelp density. This is thought to be due to diminishing intraspecific competition leading to a lower elimination of juvenile sporophytes. Data obtained suggest that total harvesting of kelp has a negative effect on the structure and species composition of kelp communities since, two years after kelp removal, communities did not attain their pre-harvest level, in spite of a quick restoring of kelp biomass. After total harvesting, filamentous rhodophycean algae began to play an important role. They can be considered as opportunistic species. These conclusions are applicable to regions where pressure from sea otters is relatively strong since, in the absence of these predators, sea urchins should negatively influence kelp restoration.

Introduction Aspects of harvesting, aquaculture and utilization of laminarian algae are widely discussed in the scientific literature (Sarochan 1962; Kizewetter 1966; Blinova and Gusarova 1971; Smith 1985, 1986; Vozzhinskaya 1982, 1986a; Nisizawa et al. 1987). Recently, aquaculture of kelp has received more interest because the yield is more controllable. On the other hand, it cannot be managed in some regions due to harsh environmental conditions, and so harvesting of natural populations is more urgent there. Although ecologically harmless mechanized methods of harvesting exist (Pogodin 1962), they are not used. Instead, drags, 'kanza' or cables (which severely damage benthic populations) are used and these literally plough over the substrata and destroy

benthic organisms (Gemp 1962; Vozzhinskaya 1982, 1986a). It is possible to use diving methods of harvesting, or to pick up kelp newly cast ashore, or to employ limited 'mowing' in the intertidal zone during low-tide. The last two methods are especially applicable in regions where harvesting policy is governed by laws protecting the natural environment, as in the Commander Islands. Off Bering Island, five species of the genus Laminaria are found. The best for harvesting is L. bongardiana. Its lamina reaches 3 m in length, common length being about 1.5 m, and its stipe does not exceed 10 cm. This species is distributed from the intertidal zone to a depth of 10-12 m, although it is concentrated in the +0.2 to 1-2 m depth range. The next species, L. dentigera, which is distributed from 0 to 25 m depth, has a high

V.V. Oshurkov & E.A. Ivanjushina

biomass and reaches 2 m in length. However, about half of its length falls on its stipe and holdfasts, so that this species is less convenient to harvest. Another two subtidal species, L. yezoensis and L. gurjanovae, do not form thickets, and are of no interest. The last species, L. longipes, forms narrow intertidal bands in the most surf-subjected sites, occupies small areas, is about 0.5 m in length and, again, is of no harvesting interest. In 1986, the mean biomass of laminarian algae off Bering Island was 3.1 ± 0.5 kg·m- 2 , and in 1991 it reached 11.3 ± 1.7 kg·m- 2 (Oshurkov et al. 1991; Oshurkov and I vanjushina, in press). This increase in laminarian abundance appears to be due to a decline in the quantity of sea urchins, which are the main consumers of kelp. In turn, the decrease in sea urchin abundance results from increased pressure by their predator, the sea otter Enhydra lutris (Oshurkov et al. 1989, 1991; Oshurkov 1990; Oshurkov and Ivanjushina, in press). Thus, as in other regions, off Bering Island man can play a role as a kelp consumer, his harvesting policy balancing the lack of kelp utilization by sea urchins so as to prevent 'overproduction' of kelp. However, the optimum intensity of harvesting must be estimated so that an amount of kelp is obtained which will neither destroy the kelp stock nor result in irreversible changes in the shallow-water communities. Prior to this study, few investigations have been undertaken concerning the effects of harvesting on the composition and structure of near-shore kelpdominated communities. This paper deals with the effect of intensity of kelp harvesting on kelp biomass restoration, and the influence of kelp removal on the species composition, abundance and distribution of other benthic organisms. Aspects of the growth and population biology of Laminaria bongardiana are discussed elsewhere (lvanjushina and Zhigadlova, in press).

Materials and methods Bering Island is situated 103 miles off the Kamchatka Peninsula at the southern border of the Bering Sea and is separated by a gulf 196 miles wide from the Near Islands of the Aleutian arc. Investigations were carried out from May 1989

96

until July 1991 on the Pacific coast of the island at its northern part. The study site is characterized by a complicated relief involving a rocky intertidal platform with many cracks (up to 2 m in depth) resembling small fjords. Four experimental plots (each of 20 m 2) were chosen in the intertidal and upper subtidal zone in May 1989 and 1990. Plots 1 and 3 were situated in rocky cracks of the basic platform (their depth was 1.0-1.5 m); plot 2 was at 8 m and plot 4 was in a rocky intertidal basin (depth +0.3-0.5 m). All three 'crack' plots were oriented differently, relative to main wind directions. Species composition, density and biomass of laminarian algae were determined at each plot before beginning the experiment. At plot 1, in 1989, all laminarian algae exceeding 15 cm in length were removed and, in 1990,50% of the area was 'mowed' randomly. At plot 2, in 1989, total mowing of kelp was carried out. In 1990, plot 2 was divided into two halves; at the first (I) total mowing was repeated, whereas the second one (11) was undisturbed. At plot 3, in both 1989 and 1990, 50% of the area was mowed randomly. At plot 4 (chosen in 1990), total mowing of plants larger than 20 cm was carried out and only juvenile sporophytes were retained. In 1990 and 1991, the abundance of Laminaria bongardiana was estimated on the rocky reef of Fedoskina Bight, 6 km away from the main study site referred to as plot 5 later in the text. From 1987 until 1991, at this bight, limited harvesting of large specimens by natives took place during June and July. During mowing, the seaweeds were detached with knives near their holdfasts, so that no regrowth of the lamina and no damage to the substrata could take place. During each year of the experiment, kelp abundance was estimated at the same time of year in order to minimize seasonal changes in biomass. During the course of the experiment, 85 samples were obtained at plot 1; 53 at plot 2; 89 at plot 3; 118 at plot 4 and 42 at plot 5. In addition, in 1990, the abundance of kelp was estimated near plot 2 (7 samples), and in 1991 near plots 3 and 4 (20 samples each). Minimal sampling area was 0.25 m 2 during the entire experiment.

Experimental kelp harvesting

In addition, every year, biological samples were obtained at plots 1 and 2 by SCUBA divers using 0.25 m 2 quadrats, in order to check for changes in the community structure and in the abundance of benthic organisms. The numbers of samples obtained and the biomass (g·m- 2) of each taxon present are given in Tables 1 and 2. Measurements involved were: mean biomass of species (or taxa); mean density of kelp species; mean biomass of the community; species richness; and species (taxa) diversity (Shannon and Weaver 1963) calculated as H' = LPi log2 Pi

where Pi represents the share of biomass of the ith species (in rare cases, taxon) in the common community biomass.

Results Plot 1 In 1989, before the beginning of the experiment, 36 taxa were recorded from the community, including 3 species of the genus Laminaria with a total biomass of 13.69 kg·m- 2 (Table 1, Fig. 2A). The dominant species was L. dentigera, and L. bongardiana was nearly absent. Phaeophytan algae (Alaria marginata), sponges (Halichondria panicea), and rhodophytan algae (Odonthalia spp.) were also abundant and amphipods and limpets (Collisella spp.) were abundant among the vagile organisms (Table 1). In the first postharvest year (1990), considerable change occurred: the biomass of L. dentigera diminished significantly, while its density increased nonsignificantly (Table 1, Fig. 2); biomass of L. bongardiana sharply increased as well as its density (Table 1, Fig. 2); the biomass of A. marginata slightly decreased, but its density rose sharply to exceed 140 specimens'm- 2 (Table 1, Fig. 2); the abundance of filamentous rhodophytan algae increased, especially Neoptilota asplenioides and Pterosiphonia hamata; the total biomass of filamentous red algae increased almost three times (Fig. 2A) and the abundance of sponges and amphipods also altered (Table I). The total biomass of the community decreased significantly, whereas species richness increased, mainly due to

rhodophytan species (Fig. lA). New species appeared in the community, including green algae (Acrosiphonia duriuscula), phaeophytan algae (Thalassiophyllum clathrus), red algae (Ptilota spp.), and others (Table 1), but there was no significant increase in the species diversity index (Fig. lA). After 50% mowing in 1990, various changes took place during the next year: the biomass of Laminaria dentigera was restored to the preexperimental level; the abundance of L. bongardiana was significantly diminished (Table 1, Fig. 2) and the biomass of Alaria marginata slightly exceeded the initial value (Table 1, Fig. 2A). On the whole, however, the pre-experimental structure and species composition of the community was not restored. As Table 1 shows, total biomass of the community increased, as compared with the 1990 level, but it did not reach the initial value; species richness increased once more and the species diversity index was higher than in 1989 though diminished compared with the previous year (Fig. lA). Green algae (Ulva sp., Cladophora fracta) and phaeophytan algae (Thalassiophyllum clathrus) disappeared from the community in 1991_ Plot 2 The pre-experimental community consisted of 34 taxa, including three species of the genus Laminaria with a total biomass of about 2.2 kg·m- 2 (Table 2, Fig. 3A). In the first post-harvest year (1990), the value of total kelp biomass was reduced compared to the pre-harvest value (Fig. 3A), and the density of laminarian species decreased significantly (Fig. 3B). Changes in the abundance of other organisms were insignificant (Table2). At the same time, the biomass of kelp near plot 2 was 3.0 ± 0.4 kg·m- 2 and this did not differ significantly from the pre-harvest value at the plot. Mean densities of Laminaria bongardiana and L. dentigera were 17.1 ± 3.1 and 1.7 ± 0.8 specimens ·m-2, respectively. At plot 2, the biomass of the rhodophytan algae Odonthalia spp. and Constantinea rosa-marinae did not change, but abundance of N. asplenioides increased significantly. Biomass of sea urchins 97

v.v.

Oshurkov & E.A. Ivanjushina

Table 1. Changes in biomass (g·m-2 ) of taxa at plot 1 from 1989 to 1991. Taxa

1989 (n = 5)

Laminaria bongardiana (Ph) L. dentigera (Ph) 13660.0 L. longipes (Ph) 30.0 Alaria marginata (Ph) 3120.0 Clathromorphum spp. (Rh) Neoptilota asplenioides (1={h 33.2 Mikamiel/a ruprechtiana (Rh) 89.1 Porphyra sp. (Rh) Palmaria stenogona (Rh) 30.1 Odonthalia spp. (Rh) 244.0 Pterosiphonia hamata (Rh) 2.6 Pleonosporium kobayashii (Rh) 5.5 Callophyllis cristata (Rh) 1.2 Corallina pilulifera (Rh) 4.1 Phycodris riggii (Rh) 12.0 Iridaea cornucopiae (Rh) 0.9 Hydrozoa Bryozoa 3.2 Chaetomorpha tortuosa (Ch) Cerithiopsis sp. (Ga) Viva sp. (Ch) 0.6 Cladophora fracta (Ch) 0.1 Halichondria panicea (Po) 808.0 Collisella spp. (Ga) 24.6 Strongylocentrotus polyacanthus (E) 13.6 Leptasterias sp. (Ast) 3.7 Lacuna reflexa (Ga) 1.5 Epheria vincta (Ga) 0.1 Vilasina pseudovernicosa (Bi) 0.1 Amphipoda 29.8 Polyehaeta 8.2 Nemertini 0.1 Aetiniaria 7.7 Dermaturus mandtii (De) 0.2 Idothea aleutica (Is) 0.5 Lorieata 0.1 Ptilota spp. (Rh) Tokidadendron kurilensis (Rh) Rhodophyta variae Acrosiphonia duriuscula (Ch) Dichloria viridis (Ph) Thalassiophyllum clathrus (Ph) Littorina sitchana (Ga) Styela clavata (Ase) Pantopoda Cucumaria vegae (Ho) Alcyonidium sp. (Br) Modiolus fena (Bi) Bossiella cretacea (Rh) Rhodoglossum phyllocarpum (Rh) Didemnum gemmiparum (Ase) Ophiopholis aculeata (Oph) Pagurus hirsutiusculus (De) Mytilus trossulus (Bi) 98

+

± 2370.0 ± 26.0 ± 1050.0

+

± ±

28.9 47.1

+

± ± ± ± ± ± ± ±

1991 (n = 10)

1990 (n = 20)

12.6 192.0 1.1 2.6 0.8 2.8 11.5 0.7

981.0 3488.0

± 247.0 ± 1589.0

2328.0 112.0 328.0 133.0 1.2 91.2 255.0 201.0 0.1 0.3 41.7

± ± ± ± ± ± ± ± ±

10.0 0.6 259.0 14.5 0.6 16.6 0.4

± ± ±

± ±

934.0 13.0 110.0 78.0 0.6 37.3 162.0 141.0 0.1 0.2 40.8

350.0 12155.0

± 193.0 ± 1284.0

4180.0 408.0 326.0 106.0

± 1319.0 ± ± ±

6.7 96.0 30.0

+ 11.2 109.0 13.5

± ± ±

7.6 54.0 6.6

+ 0.6 11.7

± ±

0.4 4.0

+

±

3.2

+ +

0.4 ± ± 0.0 ± 628.0 ± 9.2 13.7 ±

± ± ± ±

± ±

± ±

± ± ±

2.3 1.1 0.1 0.1 24.7 6.8 0.1 5.1 0.2 0.4 0.1

± ± ± ±

0.1 3.5 0.7 0.4 1.7 0.5 0.4

±

10.0 8.8 8.8 3.9 1.3 40.5 0.7

± ± ± ± ± ± ±

± ±

± ±

± ± ±

3.1 0.4 134.0 5.3 0.4 10.4 0.1 0.0 1.0 0.3 0.1 1.2 0.4 0.3

638.0 15.2 2.7 7.2 0.3 0.1 5.2 2.7 1.8 9.2 1.2 1.5

± ± ±

± ± ±

± ±

± ±

± ±

0.1 0.0 1.6 1.5 0.7 2.6 0.7 0.7

± 6.3 4.6 5.8 2.3 1.3 38.3 0.3

10.0 41.5

± ±

6.7 20.6

0.2

±

0.1

0.1 3.0 0.2

0.1

±

0.1

2.1 0.5 1.0 0.3 0.9

± ±

2.1 0.5 0.6 0.3 0.6

+ +

0.1 3.0 0.2

± 185.0 5.6 ± 2.7 ± 6.5 ±

+

± ± ± +


Table 1

(continued)

Polyclada Hapalogaster grebnitzkii (De) Nucella freysinettii (Ga) Velutina fraudatrix (Ga) Musculus minutus (Bi)

+ + + + +

+ Means that a taxon is present but only in a small amount (less than 0.1 g.m-2 ). Asc, Ascidiae; Ast, Asteroidea; bi, Bivalvia; Br, Bryozoa; Ch, Chlorophyta; De, Decapoda; E, Echinoidea; Ga, Gastropoda; Ho, Holothuroidea; Is, Isopoda; Oph, Ophiuroidea; Ph, Phaeophyta; Po, Porifera; Rh, Rhodophyta; Si, Sipuncula.

Table 2. Changes in biomass (g·m-2 ) of taxa at plot 2 from 1989 to 1991.

Taxa

1989 (n = 6)

Laminaria bongardiana (Ph) 1907.0 ± L. dentigera (Ph) 270.0 ± L. yezoensis (Ph) 20.0 ± Alaria sp. juv. (Ph) 3.3 ± Thalassiophyllum clathrus (Ph) 157.0 ± Agarum cribrosum (Ph) 1.1 ± Clathromorphum spp. (Rh) 777.0 ± Odonthalia spp. (Rh) 273.0 ± Neoptilota asp/enioides (Rh) 12.9 ± Constantinea rosa-marinae (Rh) 33.6 ± Phycodris riggii (Rh) 0.1 ± Pterosiphonia bipinnata (Rh) 0.7 ± Dichloria viridis (Ph) 6.9 ± Chaetomorpha tortuosa (Ch) 0.8 ± Ulva sp. (Ch) 3.2 ± Actiniaria 546.0 ± Stauromedusae 0.7 ± Loricata 5.5 ± Polychaeta 3.5 ± Epheria vincta (Ga) 0.3 ± Amphipoda 0.1 ± Margarites helicina (Ga) 0.1 ± Hiatella arctica (Bi) 1.5 ± S. polyacanthus (E) 11.3 ± Synascidiae 0.1 ± Asteroidea 1.0 ± Phascolosoma japonica (Si) 3.0 ± Brachiopoda 2.3 ± Velutina fraudatrix (Ga) 0.1 ± Trichotropis sp. (Ga) 0.1 ± Bryozoa 2.0 ± Plicifusus kroyeri (Ga) 3.7 ± Phoronida 41.1 ± Dermaturus mandtii (De) + Cymathere triplicata (Ph) Palmaria stenogona (Rh) Ca/lophyl/is cristata (Rh) Rhodophyta gen. sp. Cucumaria vegae (Ho)

1990 (n = 12)

1991-1 (n = 5)

1991-11 (n = 5)

851.0 1569.0 ± 375.0 9520.0 ± 2218.0 5228.0 ± 900.0 184.0 113.0 ± 76.0 652.0 ± 364.0 894.0 ± 693.0 481.0 ± 284.0 20.8 221.0 ± 129.0 70.4 ± 40.1 1.8 6.6 ± 3.8 17.4 91.0 781.0 ± 202.0 93.4 ± 28.8 78.1 ± 1.2 0.7 6.9 0.7 ± 6.9 ± 602.0 ± 157.0 453.0 426.0 ± 121.0 662.8 ± 238.6 25.9 70.5 ± 122.6 ± 36.1 95.0 238.0 ± 79.0 5.9 79.0 ± 39.6 47.7 ± 16.7 66.2 ± 49.9 15.5 7.7 33.1 ± 11.9 8.0 ± 4.1 9.8 ± 0.1 28.2 ± 18.6 0.7 7.7 ± 4.8 0.1 0.1 ± 0.3 ± 0.3 6.9 0.9 35.4 1.6 ± 92.5 ± 55.9 58.4 ± 0.8 1.9 3.8 1.3 5.5 ± 1.9 ± 347.0 110.8 ± 110.8 322.0 ± 322.0 0.7 0.9 0.9 ± 0.3 ± 0.3 3.4 4.5 1.9 9.9 ± 4.2 ± 1.3 1.9 ± 2.3 9.9 ± 4.5 1.9 1.3 4.2 ± 1.9 ± 0.1 2.3 1.3 3.7 ± 4.1 ± 0.0 0.8 ± 0.3 0.1 0.3 ± 0.6 ± 0.1 0.1 0.3 ± 0.3 + 0.8 1.4 ± 0.3 2.6 3.4 ± 3.2 4.9 ± 7.6 1.1 2.6 1.1 ± 29.4 ± 3.4 ± 3.2 1.2 1.2 0.1 1.9 3.1 ± 0.1 ± 0.1 0.9 292.1 ± 16.1 25.3 ± 18.1 76.3 ± 70.3 2.1 1.9 11.1 ± 5.7 2.3 ± 5.1 ± 5.1 2.3 0.2 0.3 ± + + 0.1 + 0.1 1.2 0.3 ± 0.3 1.9 2.1 ± 3.7 34.9 44.7 ± 13.9 37.9 ± 19.0 +* 0.2 0.2 ± + ± 5.0 ± 3.9 1.7 ± 1.2 0.7 1.1 ± 0.3 0.8 0.7 ± 2.2 ± 1.5 ± 1.2 0.1 2.4 0.1 ± 3.6 ± 99


Table 2 (continued) Nudibranchia Collisel/a spp. (Ga)· Lacuna reflexa (Ga) Halichondria panicea (Po) Porifera gen. sp. 1 (orange) Porifera gen. sp. 2 (white) Vilasina pseudovernicosa (Ga) Nemertini Ptilota spp. (Rh) Pagurus hirsutiusculus (De) Oenopota sp. (Ga) Pantopoda Hydrozoa Laminaria jurjanovae (Ph) Hommersandia palmatifolia (Rh) Halisarca dujardini (Po) Macrura gen. sp. Telmessus cheiragonus (De) Chlorophyta gen. sp. Molgula sp. (Asc) Velatocarpus pustulosus (Rh) Pleonosporium kobayashii (Rh) Mikamiel/a ruprechtiana (Rh) Puncturella sp. (Ga) Rhodymenia pertusa (Rh) Gastropoda gen. sp. Idothea aleutica (Is) Ophiopholis aculeata (Oph) Turnerella mertensiana (Rh) Rhodoglossum phyllocarpum (Rh) Kellia comandorica (Si) Polyclada Laminaria longipes (Ph)

0.1 0.1 0.8 2.7 7.6 0.6 0.3

± ± ± ± ± ± ±

0.1 0.0 0.3 2.3 7.6 0.5 0.1

0.1

±

0.1

+

11.4

+ 0.5 0.3

± ±

0.3 0.3

3.2 3.1

±

±

9.7

+

+

±

1.8

3.1

+ + 0.1 2.6 6.0 0.6 0.1 27.2 1.2 0.1

± ± ± ± ± ± ± ±

0.1 2.6 6.0 0.6 0.1 27.2 1.2 0.1

18.9

± ± ± 0.1 ± 2.0 ±

19.0 0.2

± 18.9

13.8 0.2 0.5 0.0 2.0

±

0.5

+

+ 1.5 0.9 1.3

± ± ±

1.2 0.9 1.3

+ 0.7 0.1 3.6

± ± ±

+ 16.3 0.2

0.7 0.1 3.6

± 16.3 ± 0.2 +

+ means that a taxon is present but only in a small amount (less than 0.1 g·m-2 ) * estimation of abundance of Phoronida was not carried out. For abbreviations, see Table 1.

decreased and large starfishes appeared. In 1990, sea anemones disappeared at plot 2 (Table 2). Species richness increased sharply at plot 2, but the species diversity index retained its value. Community biomass fell slightly (Fig. 1B, Table 2).

In 1991, a year after the repeated total mowing in one half of plot 2 (the 1991-1 results), the total biomass of kelp was three times as high as in 1990, and the biomass of Laminaria bongardiana had increased some six times (Table 2, Fig. 3A). The densities of the laminarian species also increased (Fig. 3B). The biomass of Odonthalia spp., Constantinea rosa-marinae, Neoptilota 100

asplenioides and starfishes diminished, but that of sea urchins and the phaeophytan alga Dichloria viridis increased, compared with the values of the preceding year (Table 2). Species richness decreased due to the disappearance of some species, but it was nevertheless higher than the initial level. Species diversity fell, however, whereas total community biomass increased significantly (Table 2, Fig. 1B). In 1991, in the non-mowed half of plot 2 (the 1991-11 results), the biomass and density of kelp species also increased, but this increase was less than in the mowed half (Table 2, Fig. 3). As in the total mowed half, a decrease in biomass of


A

"1___

/'/' /'

,/ 1

. .0

-- ------'0 -

,/

/'

B

o.

rL------~·~i, . "-

'-

"-

"-

"

11 Fig. 1. Changes in the main community characteristics from 1989 to 1991: A, plot 1; B, plot 2: I, at the 'mowed in 1990' half; 11, at the 'untouched in 1990' half. Open circles - species diversity, solid circles - community biomass, squares - species richness. Vertical lines represent ± 1 SE.

101

v.v.


A

~

I ~

B

~ 1989

1990

L. bongardiana

L. dentigera

A. marginata

Rhodophyta

1991

Fig. 2. Changes in macrophytan abundance at plot 1 from 1989 to 1991: A, mean biomass; S, mean density (density of rhodophytan algae was not estimated). Vertical lines represent ± 1 SE.

Odonthalia spp., Constantinea rosa-marinae and starfishes was observed, but, conversely, the biomass of Thalassiophyllum clathrus and white sponges increased considerably, whereas the abundance of Neoptilota asplenioides and sea urchins did not change significantly (Table 2). Species richness diminished almost to the preexperimental level, but there was no significant 102

decrease in the species diversity index (Fig. IB). The two halves of plot 2 did not differ significantly from one another in terms of mean biomass of the community or the kelp and species diversity, but they differed significantly relative to the abundance of Odonthalia spp., T. clathrus, and sea urchins (Table 2).


Plot 3 Three species of laminarian algae grew initially at this plot, i.e., Laminaria bongardiana, Alaria marginata, and Thalassiophyllum clathrus. The first one dominated the biomass and the other two were rare. In the first post-harvest year (1990), the biomass and density of L. bongardiana slightly

increased (Fig. 4), but the other two species were not found. In 1991, after the repeated 50% mowing, the biomass of L. bongardiana increased once more and significantly differed from the values of both preceding years, but its density diminished to half the level of 1990 (Fig. 4). The other two laminarian species did not appear. In 1991, near plot 3, the biomass of L. bongardiana

A

B

1989

1990

1991 (I)

1991 (11)

Fig. 3. Changes in macrophytan abundance at plot 2 from 1989 to 1991: A, mean biomass; 8, mean density. In 1991, I and" respectively represent the 'mowed' and the 'untouched in 1990' halves of plot 2. Other legends as for Figure 2. 103

v.v.


was 12.9 ± 2.1 kg·m- 2 , and the kelp density was 34.2 ± 5.8 specimens·m- 2, i.e., they did not differ significantly from the values at the experimental plot. Plot 4 A single kelp species, Laminaria bongardiana, was found at this plot. In 1991, a year after the experimental elimination of all the large specimens, both the biomass and the density of L. bongardiana increased significantly (Fig. 4). In 1991, near plot 4, the biomass of this species was 13.4 ± 1.8 kg·m- 2 and the density 51.0 ± 6.6 specimens·m- 2 , i.e., its biomass was comparable to plot 4, but its density was significantly less than at plot 4. Plot 5 The 1991 abundance of Laminaria bongardiana at this plot did not differ significantly from the values of 1990 (Fig. 4). Other laminarian species were not found.

Discussion The results obtained are contradictory. Apparently, the degree by which kelp stocks are restored is to a considerable extent due to patterns of local environmental conditions wave exposure, bottom slope, depth and mesorelief of substrata. Also, annual fluctuations in recruitment can play a great role (Vozzhinskaya 1986b; Paimeeva 1990). In the intertidal zone (plots 4 and 5) the total mowing of large specimens had no negative effect on kelp abundance. At the same time, in 1991, near plot 4, biomass of Laminaria bongardiana did not differ from that at the plot and was significantly higher than the initial biomass at this plot. Apparently, considerable annual variations in kelp productivity took place. In the upper subtidal zone (0-1.5 m, plots 1 and 3), different intensities of harvesting resulted in different effects. A year after total harvesting (plot 1), kelp biomass was not restored and partial replacement of one dominant species (Laminaria 104

dentigera) by another (L. bongardiana) took place. The next 50% mowing resulted in an increase in total kelp biomass as well as the biomass of the leading species L. dentigera. Biennial 50% mowing (plot 3) resulted in a significant increase in abundance of L. bongardiana, but the accompanying two macrophytan species disappeared and have not been restored up to present. At 8 m depth (plot 2) the results were, at first, unexpected. A year after total harvesting, total kelp biomass significantly diminished, though changes in the abundance of each of the laminarian species were not significant. In 1991, after a repeated total harvesting in one half of the plot, no further decrease of kelp biomass was observed and, indeed, contrary to expectations, the biomass of all the laminarian species increased considerably. A similar pattern was observed at the second (untouched in 1990) half of plot 2, where the abundance of kelp was slightly less compared to that of the first half. All these data lead to the conclusion that 1991 was a very productive year for laminarian algae. As expected, total harvesting of kelp resulted in a considerable decrease in kelp abundance. Nevertheless, rises of kelp biomass were observed on two occasions (plots 2 and 4 in 1991). Increase in biomass and (more important) density in kelp at these plots appears to be due to a diminished competition for light and substrata between the young plants. Increase in seaweed density after canopy removal has been observed by other investigators (Smith 1986; Engel 1990). It is accompanied by a decrease in phytobenthic diversity and, furthermore, because it increases sedimentation processes, it reduces future recruitment and the germination of kelp spores and gametophytes (Duggins et al. 1990). Up to now, the influence of sea urchin grazing or harvesting on the structure and species composition of benthic communities is not well investigated. Nevertheless, the data available show that changes in macrophytan abundance has a considerable effect on benthic communities (Day ton 1975a, b, 1985; Foreman 1977; Estes et al. 1978; Breen et al. 1982; Scheibling 1986; Duggins et al. 1990; Engel 1990; Scheibling and Raymond 1990). On the other hand, Smith (1985)


A

B

.....

0> <X)

0> T""

o0>

T""

0>

0> 0>

T""

T""

3

o0>

T""

o

0>

0> 0>

0> 0>

T""

T""

T""

4

T""

0> 0> T""

5

Fig. 4. Changes in abundance of Laminaria bongardiana at plots 3, 4, and 5 from 1989 to 1991. A, mean biomass; 8, mean density. Vertical lines represent ± 1 SE.

105


did not record irreversible changes in the community structure after a single canopy removal. The present data show that increased kelp harvesting results in considerable changes in community structure. A year after a single total mowing at two experimental plots (1 and 2) similar effects were observed, i.e., a decrease in community biomass, increase in species richness and a rise in importance of rhodophytan algae, which appear to be opportunistic species occupying the vacant substrata. At plot 1, Laminaria bongardiana also played the role of a competitive species relative to L. dentigera. Prolonged harvesting at a different intensity partly restored the kelp biomass but the summary characteristics of kelp communities have not reattained their initial values. The experiment conducted imitates, to some extent, the elimination of kelp by sea urchins. Aspects of the interactions between kelp, sea urchins and sea otters have been discussed for some time (Estes and Palmisano 1974; Breen and Mann 1976; Duggins 1980; Day ton 1985; Van Blaricom and Estes 1987; Oshurkov et al. 1991). It is known that sea urchins, in the absence of their predator (sea otters), may destroy kelp forests and turn them into so-called sea urchin barren grounds. Over-harvesting of kelp may also result in catastrophic changes to nearshore communities (Druehl and Breen 1986). On the other hand, kelp abundance may be restored due to a decrease in sea urchin numbers caused by their mass mortality, influence of predators, or other factors (Mann 1977; Breen et al. 1982; Scheibling 1986; Oshurkov and Ivanjushina, in press). It should be noted that, unlike the natural situation, the imitated phytophagan pressure did not last all year round. This was why barren grounds were not observed at the experimental plots in this study. In addition, sea urchins graze not only sporophytes but also microscopic gametophytes and so influence kelp recruitment. During the last several years, sea otter predation was constant in the area of investigation (Sevostjanov 1984; Sevostjanov and Burdin 1987) and so sea urchins were not abundant there (Oshurkov et al. 1991; Oshurkov and Ivanjushina, in press). Thus, they did not influence kelp 106

abundance. In the absence of herbivores, kelp biomass has increased significantly in recent years. Experimental mowing of large plants resulted in a further increase in kelp abundance. No doubt, in the absence of sea otters, the process of kelp restoration will be prolonged, and kelp harvesting may become impossible. Based on observations made during this study, cut kelp laminae can regrow if the cut is situated higher than the growth zone (Ivanjushina and Zhigadlova, in press). If the cut is situated in the growth zone, however, the restored laminae take an irregular shape. It is possible that the existence of 'crooked' forms of Laminaria bongardiana (f. subsessilis and f. bifurcata) at the Commander Islands is due to irregular regrowth of the badly damaged initial form, f. taeniata. Since a plant may live for two years continually restoring its damaged lamina, the most advantageous way of harvesting would appear to involve cutting the kelp laminae higher than their growth zones.

Conclusion After the experimental removal of kelp, its biomass is restored in a short period (1-2 years) depending on the intensity of harvesting. It should be noted that this process is relatively short in the absence of herbivores. In regions where the pressure of predators (sea otters) is weak, restoration processes should proceed in another way. As a whole, in the upper subtidal zone, laminarian sporophytes are highly resilient to damaging influences. After experimental harvesting, changes in the quantitative characteristics of benthic populations and kelp communities take place, i.e., lessening in the community biomass and species diversity index, an increase in species richness, and alterations in abundance and composition of benthic species. At the most wave-exposed experimental plot, a partial short-term replacement of the dominant species Laminaria dentigera by L. bongardiana was observed. Two years after kelp removal, communities did not return to their preexperimental state. We can, therefore, conclude that total harvesting of kelp has a negative influence on the community structure as a whole.


Acknowledgements

We are very grateful to our colleagues, V. V. Shalukhanov, A.V. Rzhavsky, G.G. Zhigadlova, Vu. P. Shturmina, V.V. Strelkov, O.G. Strelkova,

and A.I. Buyanovsky, for their assistance during field data collections. We are grateful to an anonymous referee for improving the English of this paper.

References

Blinova, E.1. and Gusarova, 1.S. 1971. Algae of the subtidal zone of the south-eastern coast of Kamchatka. In Transactions of TINRO, vol. 76, 139-55. Yuzhno-Sakhalinsk. (In Russian) Breen, P.A., Carson, T.A., . Foster, J.B. and Stewart, E.A. 1982. Changes in subtidal community structure associated with British Columbia sea otter transplants. Marine Ecology Progress Series 7: 13-20. Breen, P.A. and Mann, K.H. 1976. Destructive grazing of kelp by sea urchins in eastern Canada. Journal of the Fishery Research Board of Canada 233: 1278-83. Day ton, P.K. 1975a. Experimental studies of algal canopy interactions in a sea-otter dominated kelp community at Amchitka Island, Alaska. Fishery Bulletin 273:230-7. Day ton, P.K. 1975b. Experimental evaluation of ecological dominance in a rocky intertidal algal community. Ecological Monographs 45:137-59. Day ton, P.K. 1985. The structure and regulation of some South American kelp communities. Ecological Monographs 255:447-68. Druehl, L.D. and Breen, P.A. 1986. Some ecological effects of harvesting Macrocystis integrifolia. Botanica Marina 229:97-103. Duggins, D.O. 1980. Kelp beds and sea otters: an experimental approach. Ecology 61 :447-53. Duggins, D.O., Eckman, J.E. and Sewell, A.T. 1990. Ecology of understore kelp environments. 11. Effect of kelp on recruitment of benthic invertebrates. Journal of Experimental Marine Biology and Ecology 143:27-45. Engel, S. 1990. Ecological impact of harvesting macrophytes in Halverson Lake, Wisconsin. Journal of Aquatic Plant Management 28:415. Estes, J.A. and Palmisano, J.F. 1974. Sea otters:

their role in structuring nearshore communities. Science 1985: 1058-60. Estes, J.A., Smith, N.S. and Palmisano, J.F. 1978. Sea otter predation and community organization in the western Aleutian Islands, Alaska. Ecology 59:822-33. Foreman, R.E. 1977. Benthic community modification and recovery following intensive grazing by Strongylocentrotus droebachiensis. Helgolander Wissenschaftliche Meeresuntersuchungen 30:468-84. Gemp, K.P. 1962. Seaweeds and sea grasses stocks in the White Sea and means of their further harvesting. In Proceedings of the Conference of Workers in the Algal Industry of the USSR, vol.l, 75-86. Arkhangelsk. (In Russian) Ivanjushina, E.A. and Zhigadlova, G.G. In press. Aspects of growth and population biology of Laminaria bongardiana off Bering Island (Commander Islands). Biologiya Morya, Vladivostok. (In Russian) Kizewetter, LV. 1966. Harvesting and treatment of seaweeds in Primorje. Vladivostok: Dal'izdat. (In Russian) Mann, K.H. 1977. Destruction of kelp-beds by sea urchins: a cyclical phenomenon or irreversible degradation? Helgolander Wissenschaftliche Meeresuntersuchungen 30:455-67. Nisizawa, K., Noda, H., Kikuchi, R. and Watanabe, T. 1987. The main seaweed foods in Japan. Hydrobiologia 151 :5-29. Oshurkov, V.V. 1990. Modification of the nearshore benthic ecosystem off Bering Island caused by the sea otter predation. In Marine Mammals, 228-9. Proceedings of the 10th conference on investigations, protecting and rational treatment of marine mammals in the USSR. Moscow. (In Russian) 107

v.v.


Oshurkov, V.V., Bazhin, A.G., Lukin, V.I. and Sevostjanov, V.F. 1989. Sea otter predation and structure of benthic communities off the Commander Islands. Biologiya Morya, Vladivostok 6:50-60. Oshurkov, V.V., Bazhin, A.G. and Lukin, V.I. 1991. Changes in benthic structure off the Commander Islands under the impact of sea otter predation. In Natural resources of the Commander Islands. Issue 2, 171-85. Moscow: Izdatelstvo MGU. (In Russian) Oshurkov, V.V. and Ivanjushina, E.A. In press. Long-term changes in the shallow-water communities off Bering Island (Commander Islands). In Proceedings of the USSR-USA Workshop Group on Sea Otters (ed. G.R. Van Blaricom and A.M. Burdin). Paimeeva, L.G. 1990. Long-term dynamics and state of stock of Laminaria japonica flongipes (Miyabe et Tokida) Petf. in the northern Primorje. In Abstracts of the Report Session of TINRO Based on Results of 1989, 50-2. Vladivostok: TINRO. (In Russian) Pogodin, L.L. 1962. Means of further mechanization of harvesting of seaweeds. In Proceedings of the Conference of Workers in the Algal Industry of the USSR, vol.l, 75-86. Arkhangelsk. (In Russian) Sarochan, V.F. 1962. Stock of seaweeds and means of further development of seaweed harvesting in the Far Eastern seas of the USSR. In Proceedings of the Conference of Workers in the Algal Industry of the USSR, vol.l, 32-44. Arkhangelsk. (In Russian) Scheibling, R.E. 1986. Increased macroalgal abundance following mass mortalities of sea urchins (Strongylocentrotus droebachiensis) along the Atlantic coast of Nova Scotia. Oecologia 68: 186-98. Scheibling, R.E. and Raymond, B.G. 1990. Community dynamics on a subtidal cobble bed following mass mortalities of sea urchins. Marine Ecology Progress Series 63: 127-45.

108

Sevostjanov, V.F. 1984. Results of investigations on the sea otter population carried out from 1979 until 1982 at the Commander Islands. In Investigations on Marine Mammals of the Northern Pacific in 1982183, 63-8. Moscow: VNIRO. (In Russian) Sevostjanov, V.F. and Burdin, A.M. 1987. Perspectives in growth of the Bering island group of the population of sea otter from the Commander Islands. In Sea Otters and Fur Seals of the Commander Islands, 15-22. Petropavlovsk-Kam-chatsky: Dal' giz. (In Russian) Shannon, C.E. and Weaver, W. 1963. The Mathematical Theory of Communication. Urbana: University of Illinois Press. Smith, B.D. 1985. Recovery following experimental harvesting of Laminaria longicruris and L. digitata in southwestern Nova Scotia. Helgolander Wissenschaftliche Meeresuntersuchungen 39:83-101. Smith, B.D. 1986. Implications of population dynamics and interspecific competition for harvest management of the seaweed Laminaria. Marine Ecology Progress Series 33:7-18. Van Blaricom, G.R. and Estes, J.V. (eds.). 1987. The Community Ecology of Sea Otters. Berlin: Springer-Verlag. Vozzhinskaya, V.B. 1982. Influence of anthropogenic factors on benthic phytocoenoses of the Solovetzky Arc (the White Sea). In Problems of Ecology of the White Sea, Abstracts of the Conference, 602. Arkhangelsk - Solovki. (In Russian) Vozzhinskaya, V.B. 1986a. Benthic Macrophytes of the White Sea. Moscow: Nauka. (In Russian) Vozzhinskaya, V.B. 1986b. Monitoring of seaweeds of the White Sea. In Ocean Monitoring, 158-61. Moscow: Izdatelstvo lOAN USSR. (In Russian)


BARNACLES AS BIOMONITORS OF TRACE METALS IN THE COASTAL WATERS NEAR XIAMEN, CHINA Philip S. Rainbow,! Huang Zongguo,2 Yan SongkaP and Brian D. Smith! ISchool of Biological Sciences, Queen Mary and Westfield College, Mile End Road, London El 4NS, England. 2Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China.

Abstract The barnacles Balanus amphitrite amphitrite Darwin, Balanus uliginosus Utinomi (= B. kondakovi Tarasov and Zevina) and Tetraclita squamosa (Bruguiere) have been used as biomonitors of Zn, Cu, Cd, Pb, Cr, Ni and Ag in coastal waters of Fujian Province, China in September 1991. Analysis of Covariance was used to allow for size effects in intraspecific comparisons of the eight sites investigated. The three barnacle species occupy a range of coastal habitats, and provided consistent and complementary results on metal contamination near Xiamen and Quanzhou. Contamination gradients were particularly evident for zinc and copper at Xiamen. The three barnacle species have great potential as widespread mono specific biomonitors worldwide (B. amphitrite), throughout the lndo-Pacific (T. squamosa) and in Southeast Asian estuaries (B. uliginosus).

Introduction Work in Hong Kong (Phillips and Rainbow 1988; Chan et al. 1990; Rainbow and Smith 1992) investigated the suitability of barnacles as biomonitors of trace metals in coastal waters of the Far East. Barnacles were shown to be excellent biomonitors of local metal availabilities after allowance for body size effects, with the potential in the case of the more widespread species to act as biomonitors throughout much of the subtropical and tropical lndo-Pacific (Phillips and Rainbow 1988; Chan et al. 1990). This comparative study extends the Hong Kong work further afield to Fujian Province, China. It centres on Balanus amphitrite (strictly Balanus amphitrite amphitrite Darwin), a cosmopolitan species (Henry and McLaughlin 1975; Newman and Ross 1976) also used in the Hong Kong studies in 1986 (Phillips and Rainbow 1988; Ch an et al. 1990) and 1989 (Rainbow and Smith 1992). Another species from the Hong Kong studies, Tetraclita squamosa (Bruguiere), more typical of marine wave-washed shores, has also been used

here for comparison, with the addition of a further (more estuarine) species not previously studied as a biomonitor. This latter species is identified as Balanus uliginosus Utinomi in China, although Henry and McLaughlin (1975) preferred the name Balanus kondakovi Tarasov and Zevina for the same species (see Rainbow et al. 1989). B. uliginosus is, however, used here for reasons of familiarity to local biologists in China where the barnacle is common in low salinity estuarine habitats. Given that trace metals typically enter coastal waters via anthropogenic effluents into rivers and estuaries, the investigation of the suitability of an estuarine barnacle as a biomonitor is relevant and timely. Furthermore, B.uliginosus has a wide distribution in the Far East from southern Japan to India (Henry and McLaughlin 1975; Lewis 1985; Rainbow et al. 1989), and has the potential to be used as a metal biomonitor throughout Southeast Asia. Barnacles (Table 1) were collected from six sites in the immediate vicinity of Xiamen, Fujian Province, and from a further two sites nearer Quanzhou to the north (Fig. I). Xiamen is an

P.S. Rainbow, Z.G. Huang, S.K. Van & B.O. Smith

industrial port of approximately one million inhabitants, whereas Quanzhou is smaller with about 250,000 people. The choice of a second (potentially control) location in addition to Xiamen was considered necessary in case the coastal region of Xiamen might itself be locally atypical in terms of metal bioavailabilities. Balanus amphitrite was available at all eight sites, Tetraclita squamosa at the three more marine sites at Xiamen, and Balanus uliginosus at the lower salinity sites of Hai Cang and Song Yu affected by the Jiu Long River opposite Xiamen, and at Inner Houzhu and Outer Houzhu at the mouth of the Luo Yang River by Quanzhou (Table 1, Fig.

Quanzhou the average monthly salinity varies from 13%0 (July) to 32%0 (April) as a result of the flow of the Luo Yang River (Fig. 1), the September mean salinity being 27%0. The survey, therefore, covers sites along a gradient away from a potential contamination source (Xi amen Effluent Outfall), and sites along gradients of increasing salinity with possible physico-chemical effects on metal bioavailabilities (Phillips and Rainbow 1993).

1).

Barnacles were collected from either a pier or rocks in the eulittoral zone at 8 sites between 4 and 9 September 1991 (Table 1), and frozen on return to the laboratory. Barnacles were then identified and individual bodies of the largest available specimens dissected out using stainless steel instruments, before a brief rinse in distilled water. In the case of Balanus amphitrite, two groups of ten samples, each sample consisting of ten pooled individual bodies, were taken for analysis. For Balanus uliginosus, two groups of ten pooled samples (five bodies each) were used from Hai Cang, Inner and Outer Houzhu, but only four bodies were pooled from each of the Song Yu samples as a result of the lower abundance of barnacles there. Individual bodies of Tetraclita squamosa constituted each of the samples in the two groups of ten.

Materials and methods

During low tide at the July height of the summer wet season the water at Hai Cang is essentially the freshwater of the Jiu Long River, but surface water salinity there in September averages 18%0. September mean surface water salinities increase seawards to 29%0 at Song Yu, 30%0 at Gulang Yu and the Third Institute of Oceanography and 31 %0 at Huli Fort (Fig. 1), these figures being good approximations of yearly mean salinities at these sites. The site labelled Effluent Outfall at Xiamen (Fig. 1) receives drainage from a large lagoon, itself in a position to receive much anthropogenic domestic and industrial effluent from the city. The salinity of the harbour water by this outfall annually ranges from 25 to 32%0 with no significant freshwater input from the north of Xiamen. At Houzhu near

Table 1. Collection details of barnacles sampled. Site

Date

Barnacle species collected

Xiamen region Hai Cang (pier) Song Vu (pier) Gulang Vu (rock) Effluent outfall (pier) Third Institute of Oceanography (rock) Huli Fort (rock)

5 8 9 8 4 7

Sept. Sept. Sept. Sept. Sept. Sept.

1991 1991 1991 1991 1991 1991

Ba/anus Ba/anus Ba/anus Ba/anus Ba/anus Ba/anus

amphitrite, amphitrite, amphitrite, amphitrite amphitrite, amphitrite,

Ba/anus uJiginosus Ba/anus uJiginosus Tetraclita squamosa Tetraclita squamosa Tetraclita squamosa

Quanzhou region Inner Houzhu (pier) Outer Houzhu (pier)

110

6 Sept. 1991 6 Sept. 1991

Ba/anus amphitrite, Ba/anus uJiginosus Ba/anus amphitrite, Ba/anus uJiginosus

Metal biomonitoring in Xiamen

CHINA Quanzhou

/ Xia:n;e~ .;;...:;.:r

..... ~ 'Ho~g Kong

(J" // . ..'

TAI~AN

5km

5km

XIAMEN

~ 118~.·: ~ ..... ". '.' .-. ". .~ '.'

........ '"..

-

118°05

1

1180 10'

.

Fig. 1. Locations of six sampling sites in the Xiamen area and two near Quanzhou (larger inset) as listed in Table 1. Smaller inset shows positions of Xi amen and Quanzhou on the coast of China.

The samples of either bodies or pooled bodies were dried in pre-weighed acid-washed plastic vials to constant weight at 60°C before digestion at 100°C in conc. nitric acid (Aristar grade, BDH Ltd). One of the two groups of 10 digests for each species at each site was made up to 5 mL, the other to 2 mL with double-distilled water. Digests (or dilutions thereof) were analysed for Zn, Cu, Cd, Pb (5 mL digests) and Cr, Ni, Ag (2 mL digests) on an IL 157 Atomic Absorption Spectrophotometer (AAS) with flame atomization

and background correction. Ag measurements were made immediately on completion of digestion to reduce the danger of silver depositing from nitric acid solution. Throughout analyses, checks were made using between 3 and 6 aliquots of each of two certified reference materials (Table 2). Agreement was considered satisfactory. All metal concentrations are quoted in Jlg g-l (ppm) dry weight.

111

""U

o

I\)

::D

III

5'

0"

o

-~ N

Cv :::L c::

III ::J

co

en ~

-

Asian Marine Biology 10

Asian Marine Biology Series (v. 12)

Advances in Marine Biology, Volume 10

Marine Biology

Marine Biology

Marine Biology

Marine Biology

Biology of Marine Birds (Marine Biology)

Marine Mammals: Evolutionary Biology

Advances In Marine Biology

Biology of Marine Birds

Biology of Marine Fungi

Marine Mammals - Evolutionary Biology

Marine Biology , Seventh Edition

Introduction to Marine Biology

Oceanography And Marine Biology

Oceanography And Marine Biology

Advances In Marine Biology, Volume 46 (Advances in Marine Biology)

Advances in Marine Biology, Volume 44 (Advances in Marine Biology)

Advances In Marine Biology, Volume 51 (Advances in Marine Biology)

Advances in Marine Biology, Volume 41 (Advances in Marine Biology)

Advances In Marine Biology, Volume 53 (Advances in Marine Biology)

Advances in Marine Biology, Volume 39 (Advances in Marine Biology)

The Biology of Marine Plants

Molecular Biology In Marine Science

Methods in Reproductive Aquaculture: Marine and Freshwater Species (Marine Biology)

Biology of Northern Krill (Advances in Marine Biology, Volume 57)

Oceanography and Marine Biology: An Annual Review, Volume 45 (Oceanography and Marine Biology)

Biology of the Three-Spined Stickleback (Marine Biology)

Advances in Marine Biology, Volume 54

Asian Marine Biology 10

Asian Marine Biology Series (v. 12)

Advances in Marine Biology, Volume 10

Marine Biology

Marine Biology

Marine Biology

Marine Biology

Biology of Marine Birds (Marine Biology)

Marine Mammals: Evolutionary Biology

Advances In Marine Biology

Biology of Marine Birds

Biology of Marine Fungi

Marine Mammals - Evolutionary Biology

Marine Biology , Seventh Edition

Introduction to Marine Biology

Oceanography And Marine Biology

Oceanography And Marine Biology

Advances In Marine Biology, Volume 46 (Advances in Marine Biology)

Advances in Marine Biology, Volume 44 (Advances in Marine Biology)

Advances In Marine Biology, Volume 51 (Advances in Marine Biology)

Advances in Marine Biology, Volume 41 (Advances in Marine Biology)

Advances In Marine Biology, Volume 53 (Advances in Marine Biology)

Advances in Marine Biology, Volume 39 (Advances in Marine Biology)

The Biology of Marine Plants

Molecular Biology In Marine Science

Methods in Reproductive Aquaculture: Marine and Freshwater Species (Marine Biology)

Biology of Northern Krill (Advances in Marine Biology, Volume 57)

Oceanography and Marine Biology: An Annual Review, Volume 45 (Oceanography and Marine Biology)

Biology of the Three-Spined Stickleback (Marine Biology)

Advances in Marine Biology, Volume 54

Recommend Documents