FRONTISPIECE. Some of the major zooplankton of the south-eastern. Magnification is. coastal waters of Tasmania. approximately 4 times.

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2 FRONTISPIECE Some of the major zooplankton of the south-eastern coastal waters of Tasmania. Magnification is approximately 4 times.

3 STUDIES Oll THE ZOOPLANKTON AND HYDROLOGY OF SOUTH-EASTERN COASTAL WATERS OF TASNANIA by NYAN TAW, B.Sc. (Rangoon) Submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy. UNIVERSITY OF TAS u\l;[ih HOBART NOVlliBER, 1975

4 Except as stated herein, this thesis contains no material which has been submitted for the award of any other degree in any University and to the best of my knowledge and belief, contains no material \'Jhich has previously been written or published by any other person, except where due reference is made in the text of the thesis. The systematic part (Section I of this thesis) has been submitted and accepted for publication by the Papers and Prooeedings of the Royal Society of Tasmania. Two new species of zooplankton discovered during the study have been described in separate papers. A brief account of part of Section.III on the water movement incorporated with the heavy metal pollution which has been accepted for publication by Search is submitted in the thesis. These supporting papers are submitted here as Appendix II. November

5 CONTENTS Page AC1\..il(X'LEDGEMEN'I'S i SUMtJ,RY iii VOLUEE I SECTION I THE ZOOPLANKTON OF THE SOUTH-EASTERN COASTAL IIATERS OF TASt'UlNIA INTRODUCTION SOURCE OF YUl TERIALS AND METHODS SYSTEEAT ICS pecies List Copepoda Key to the genera 0 f Calanoida Calanoida Calanidae Eucalanidae Paracalanidae Pseudocalanidae Aetideidae Euchaetidae Phaennidae Scoleci thricidae Ce t n ropagl ae 'd Metridiidae Temoridae Pseudodiaptomidae Lu ci cutiidae Heterorhabdidae Candaciidae PonteUidae Acartiidae

6 Cyclopoida Oithonidae Oncaeidae Harpacticoida Tachidiidae Euphausiacea vecopoda Sergestidae Chaetognatha Tunicata?yrosomida Cye lomyaria Desmomyaria REFERENCES VOLUHE II SECTIOIi II 'lhe DISTR IBUT IO,: OF ZOOP:::.AlIKTOll OFF THE EAST COAST OF TAS ia;nj. AND THEIR VALUE AS BIOLOGICAL I: J ICATO.iS S=:CTIO..I :ill.60'jpla'ii<toli Au') HYDROLOGY OF It,SHORE COASTAL.:.,'CERS OF SOUTH-EAS'i'ERN TASMANIA....., SECTIOll IV ZOOPLANKTON AiiD HYDROLOGY OF DEHViENT ESTUARY.. 195

7 APPEHlJIX I - Raw Data - East Coast Study Raw Data - Inshore Coastal Study Raw Data - Derwent futuary Study A PPENDIX II - Supporting Papers A New Species of Labidocera (Copepoda:Calanoida) from Tasmania and its Postnaupliar Developmental Staees. Aust. J. mar. Freshwat. Res., 1974j 25: A New Species of Sagitta (Chaetognatha) from D'Entrecasteaux Channel, Tasmania. Pap. Froc. R. Soc. Tasm., 1975, 109: (in press) 3. Relative Composition of Zooplankton Groups as an Indication of Water Movement in the Inshore Coastal Waters of South-east Tasmania. Search, 1975, 6 (11-12): (in press)

8 i ACKNOViLEDGEMEN'I'S I Vlould like to thank the following who have helped me throughout my study period: My Supervisor, Dr. E.R. Guiler for suggesting this study, his encouragement, and critically reading the draft of this thesis; Professor B.Johnson and Dr. J.L. Hickman for their encouragement and keen interest in the work; Niss Khin Khin U for bringing to my attention an unrecorded Copepod specimen; the skipper of Zoology Department Research Vessel "Neotrigonialt, Hr. 'ras Sward for his help in the field; Mr. P. Round, for his technical assistance in constructing the counting disc and adjustable base; fir. R.G. V!heeldon, our Laboratory Hanager, for his ready help; and to the staff and members of the Zoology Department, University of Tasmania, for their help in many ways. Dr. T. Dix, Head of Sea Fisheries Division, Tasmanian Department of Agriculture, for the permission to study the zooplankton samples; and also to the staff and members 0 f the Sea Fisheries Division, particularly Nr. D. C. ';;01 fe, for their help in many ways. Dr. A.G. Nichols for his helpful advice on the taxonomic nork on the Copepods in the early stages; Dr. D.J. Tranter and Er. F.B. Griffiths of the Division of Fisheries and Oceanography, C. S.I.R.O., Cronulla, for their helpful suggestions and the loan of some reference specimens.

9 11 Dr. G.N. Lance, Chief, Division of Computing Research, C.S.I.R.O., Canberra, for helpful discussion and the Computer analysis; Dr. D.A. Ratkowsky, Division of Hathematical Statistics, C.S.I.R.O., Tasmanian Regional Laboratory, Hobart, for helpful discussion and reading the draft of the statistical part of this thesis. Finally, Hrs. L. Andersch, for typing this thesis. This work has been carried out while the author held a Colombo Plan Fellowship for which he is grateful.

10 iii 'fhe zooplankton and hydrology of the south-eastern coastal waters of Tasmania - Coastal waters off the East Coast, Insbore coastal waters and the Derwent River Estuary are investi[,ated. 'rhe ZOOPLANKTON : SYSTEHATICS Zooplankton species found during the studies are recorded, illustrated, and discussed taxonomically where appropriate. A orief account is given of the distribution of the 71 Pelagic Copepods, 8 Euphausids, 1 Sergestid, 11 Chaetognaths and 7 Pelagic Tunicates. Except for 2 Copepod species which are assigned to a genus, the remainder are posi ti vely identified. i'mongst the species recorded, 22 Copepods are new to Australian waters whereas 38 Copepods, 1 Tasmania. Euphausid and 2 Chaetognaths are new records for Keys to the genera and species are also iven. ThE DISTiiIBUTION OF ZOOPLANKTON OFF THE EhST COAST AND THEIR VALUE ;..5 BIOLOGICAL INDICATORS l.'en Cruises when tv/elve Stations were usually operated durin6 each Cruise, totalling 89 Stations from August 1971 to ;ay 1973 Vlere made for surface samples off the Es.st Coast. Thirty-five species, mainly based on their preferences for depth or temperature/salinity are selected and analysed from groupins of species and Stations by the computer program DIVINFRE.six types of water masses involving three water masses characterized by five species-groups such as, (i) Coastal; (ii) mixed Coastal and Sub-tropical; (iii) mixed Coastal and.::5ub-antarctic; (iv) mixed Sub-tropical and Sub-antarctic; (v) Sub-tropica 1; and, (vi) Sub-antarc tic, are found 0 ff eastern Tasmania.

11 iv Some literature contradictions relating to the position of the Sub-tropical Convergence and salinity of Sub-antarctic waters are discussed and it was found that the convergences oscillate along the East Coast with seasons. ZOOPLANKTON AND HYDROLOGY OF INSHORE COASTAL WATERS. Three Stations in inshore waters were operated at monthly intervals for a period of 12 months from August 1971 to July 1972, collecting samples from surface, 10m and 20m depths during day and night. Seasonal diurnal vertical distribution of mat and biomass for the 3 Stations are given and discussed. of the species Seasonal zooplankton composition for the Station at the mouth of the Derwent Estuary is given. Relative composition of indicator zooplankton species groups (inshore coastal, coastal and oceanic) are used to determine the influence of estuarine and intrusion of oceanic waters to the region. The possible oceanic waters involved and effects of movement of waters on the accumulation of heavy metals in oysters found in the Derwent Estuary and adjacent waters are mentioned. Such influences are possibly the main factors affecting the seasonal cycles of the zooplankton composition and biomass. ZOOPLANKTON AND HYDROLOGY OF THE DERWENT ESTUARY Collections from two Cruises, on 1st October 1973 and 23rd April 1974 when 10 Stations extending 50 kilometres upstream were operated during each Cruise, are studied. Hydrologically, the region covers from freshwater to marine, 17 zooplankton species representing freshwater, estuarine and marine environment being found. l'he results are compared with those of previous and similar hydrological and ecological studies.