Census of Marine Zooplankton (CMarZ)
Cooperative Project
Database for Zooplankton collected
during International Indian Ocean
Expedition (IIOE) 1960-65
Prepared by
VIJAYALAKSHMI R. NAIR
Principal Investigator
HB/50, Vijaya
South Bridge Avenue, Panampilly Nagar
Kochi 682036, Kerala, India.
Telephone/ Fax : 00-91-484-2316999
e-mail : vijayalakshmi40@hotmail.com
September 2005
Census of Marine Zooplankton (CMarZ)
Cooperative Project
Database for Zooplankton collected
during International Indian Ocean
Expedition (IIOE) 1960-65
Awarded by :
Alfred P. Sloan Foundation
Through CMarZ
University of New Hampshire
NH – 03824 – 3585
U.S.A.
Principal Investigator
:
Vijayalakshmi R. Nair
University contact
(Principal Investigator)
:
Ann C. Bucklin
Professor
Ocean Process & Analysis Laboratory
University of New Hamsphire
Morse Hall, Room 142
Durham, NH 03824
(Present address :
Ann Bucklin
Professor and Head, Department of Marine Sciences
Director, Marine Sciences and Technology Center
University of Connecticut - Avery Point
1080 Shennecossett Road
Groton, CT 06340 USA)
September 2005
ii
CONTENTS
Page No.
Acknowledgements
Summary
List of Tables and Figure
i
ii
iii
1.
1.1
1.2
INTRODUCTION
Indian Ocean
International Indian Ocean Expedition
1
1
1
2.
OBJECTIVES
2
3.
3.1
3.2
3.3
APPROACH STRATEGY
IIOE zooplankton collections
Data source
Presentation
2
2
3
3
4.
4.1
4.2
4.2.1
4.2.2
4.2.3
4.3
4.3.1
4.3.2
4.3.3
DATABASE
Basic data
Data on subsorting
Copepods
Decapods
Fish larvae
Data at species level
Copepods
Ostracods
Chaetognaths
4
4
4
4
5
5
6
6
6
6
5
REFERENCES
7
iii
ACKNOWLEDGEMENTS
I record my grateful thanks and appreciation to :
1.
Alfred P. Sloan Foundation for financial support.
2.
Dr. Ann C. Bucklin, Professor, University of Connecticut, CT for entrusting
me with this task and necessary support and encouragement.
3.
Dr. Rosamma Stephen, Expert on Copepoda for her contribution to
copepod part of the report and also for her assistance in compiling basic
data on zooplankton.
4.
Dr.C.B.Lalithambika Devi, Expert on Fish larvae for her contribution to
fish larvae part of this report.
5.
Zooplankton experts for their invaluable contribution to IIOE database.
6.
Late Dr.N.K.Panikkar, first Director, NIO for his vision and guidance to
Indian participation in IIOE.
7.
All the participants of IIOE cruises and NIO staff who analysed the
zooplankton samples.
8.
Mrs. Mallika Sivaraman for secretarial assistance
i
SUMMARY
Zooplankton samples collected during International Indian Ocean Expedition
(IIOE) 1960-65 are by far the largest and the most important collections from the
Indian Ocean in the world today.
Though several experts spent decades to study
various groups of zooplankton, these valuable data have not been computerized to
make permanent records. Hence a database for IIOE zooplankton is initiated as a
cooperative project of CMarZ and a part of the IIOE data have been digitized.
During IIOE 1548 standard zooplankton samples were collected covering the
entire Indian Ocean. The database is prepared based on published information on
these zooplankton samples. Three sets of Tables are made (1) Basic data on
zooplankton volume, total population and all the 54 taxa found in the collections. (2)
Data emerged from subsorting of copepods, decapods and fish larvae (3) Species
level data for chaetognaths for entire Indian Ocean and ostracods for northern
Indian Ocean.
ii
List of Tables
Table 1 -
Station details, zooplankton volume, total population and population of
most common groups represented in IIOE collections. Volume and
population presented as ml and number per standard haul
respectively.
Table 2 -
Population for remaining taxa of zooplankton found in the IIOE
collections. Population represented as number per standard haul.
Table 3 -
Population of different taxa of copepods subsorted from IIOE
zooplankton collections. Population represented as number per
standard haul.
Table 4 -
Different groups of decapods subsorted from IIOE zooplankton
collections. Population represented as number per standard haul.
Table 5 -
Population of 53 groups of fish larvae sorted from IIOE collections.
Population represented as number per standard haul.
Table 6 -
Population of different families of Pleuronectiformes larvae subsorted
from IIOE collections. Population represented as number per standard
haul.
Table 7 -
Data on species of Calanidae recorded from IIOE zooplankton
collections. Population represented as number per standard haul.
Table 8 -
Data on ostracod species recorded from the northern Indian Ocean,
north of 10°S. Population represented as number per standard haul.
Table 9 -
Data on chaetognath species recorded from the entire Indian Ocean.
Population represented as number per standard haul.
List of Figures
Figure 1 -
Map showing location of IIOE stations.
iii
1.
INTRODUCTION
1.1
Indian Ocean
Indian Ocean has an area of 73.4 x 106 Km2 (excluding adjacent seas),
volume of 291.03 x 106 Km2 and an average depth of 3963 m (Sverdrup et al.,
1942).
Morphologically Indian Ocean is land locked in the north and does not
extend into the cold climatic regions of north.
This causes an asymmetrical
development of its structure and circulation, which is most obvious in the
development of the huge layers of extremely low oxygen content in the Arabian Sea
and Bay of Bengal. Indian Ocean is the only area of the world Oceans with biannual reversal of surface winds (monsoons) and currents. Indian Ocean is also
one of only two areas (the other such area is eastern-tropical Pacific Ocean) which
has been actively contributing to the phenomenon of global change by producing in
its oxygen -poor mid- depth, considerable volumes of several green house gases
and ultimately releasing them to the atmosphere. The Hydrochemical Front at 10°S
separates the monsoon gyre north of 10°S from the subtropical gyre of southern
Indian Ocean. It separates low-nutrient, high oxygen content waters of subtropical
gyre from high nutrient low oxygen content waters of monsoon gyre (Wyrtki, 1973).
1.2
International Indian Ocean Expedition (IIOE, 1960-65)
Indian Ocean was the least known area of the World Oceans until the
International Indian Ocean Expedition (IIOE) 1960-65. IIOE was a multinational
venture for the systematic exploration of the entire Indian Ocean. Nine countries
and eighteen research vessels participated in IIOE. The zooplankton investigations
were the most successfully co-ordinated part of the biological programmes of the
IIOE. These International collections deposited at the Regional Centre of National
Institute of Oceanography, Kochi, India, are by far the largest and the most
important zooplankton collections from the Indian Ocean in the world today. The
Indian Ocean Biological Centre at Cochin and later the National Institute of
Oceanography (NIO), Goa in 1966 were established to consolidate all activities
connected with IIOE and also for organizing future investigations in all the basic
aspects of Oceanography.
1
2.
OBJECTIVE
Zooplankton samples collected during the IIOE are archived at the regional
Centre of National Institute of Oceanography, Kochi. Several experts, both Indian
and foreign, spent decades to study the taxonomy, species diversity and
biogeography of various groups of zooplankton. Though several publications and
doctoral theses had come out of the study, even the basic information have not
been computerized to make permanent records. The project aims to preserve a
part of the enormous amount of data by digitizing the data scattered through
different sources.
3.
APPROACH STRATEGY
3.1
IIOE zooplankton collections
During IIOE zooplankton collections were made between 25°N and 45°S lat.
and 30-120°E long.
Sampling covered
the entire Indian Ocean with better
coverage north of 10°S. Though 1927 samples were collected during IIOE,
zooplankton data for 1548 standard hauls were considered to be comparable and
these alone were utilized for all publications. A standard haul is defined as an
Indian Ocean Standard net (Currie, 1963) collection of zooplankton in water column
under 1 m2, the stratum sampled being the upper 200m in deeper water and the
entire water column where the sounding is less than 200m. Hence for this database
also 1548 standard hauls alone are considered.
The monsoon is a characteristic feature of the north Indian Ocean, north of
10°S.
During Southwest (SW) monsoon period (April 16-15 October) cyclonic
circulation develops in the surface waters and water movement is from west to east.
The wind direction is reversed during Northeast (NE) monsoon period (October 1615 April) and the gyre becomes anticyclonic and circulation becomes east to west.
This type of circulation leads to shifting of population maxima of zooplankton in
accordance with the current pattern.
If the samples are segregated based on
monsoon or day/ night the number of samples for each category is sufficiently high.
2
3.2
SW monsoon
-
836
NE monsoon
-
712
Day samples
-
826
Night samples
-
722
Data source
This database is prepared based on the published information on
zooplankton. The basic details of these collections were reported in a series of
collected reprints (IIOE, 1965-72), and handbooks & atlases (IIOE, 1969-73). The
proceedings of the symposia on Indian Ocean (1969), The Biology of the Indian
Oceans (1973), and Warm Water zooplankton (1977) covered substantial
information on zooplankton of the IIOE. Rao et al., (1981) and Nair (2001) reviewed
reports on IIOE zooplankton investigations.
The other sources referred for the
present database are that of Nair (1977), George and Nair (1980), Stephen (1998),
and Stephen et al. (1992).
3.3
Presentation
The location of stations is shown in the Map. The full details of the stations
namely serial number, vessel, cruise, station number, latitude, longitude, date, time,
day / night, year and depth, are given in Table 1. In the following Tables only serial
number is repeated. However, in Table 5 on fish larvae, samples were selected
from specific areas and hence Latitude, Longitude and marsden square numbers
are given. The sequence followed is similar to the one given in IIOE Handbook I
(1969). The biomass (volume) and population density are presented respectively as
ml and number per standard haul as per the recommendation (IIOE Handbook I,
1969).
4.
DATABASE
4.1
Basic data :
Digitised entire basic data on zooplankton for 1548 standard hauls.
A total of 54 taxa are represented in the collections. Table 1 covers the details for
the stations, zooplankton volume, total number of organisms and population for
major groups namely copepods, chaetognaths, decapods, ostracods, amphipods,
3
euphausiids, tunicates (copelates, pyrosomids, salps and doliolids), fish larvae and
fish eggs. Table 2 presents the population for 32 taxa of zooplankton found in the
IIOE collections.
Zooplankton biomass in the Indian Ocean indicates that values are the
highest in the Arabian Sea particularly off Somali coast and the coast off Saudi
Arabia. Zooplankton biomass, total population and population density for major
groups of zooplankton show gradual decrease from north to southern part of the
Indian Ocean (IIOE, 1969-73 ; Nair, 2001).
4.2
Data on subsorting:
4.2.1 Copepods
Subsorting of copepods was undertaken for 340 stations as per the
recommendation of the Advisory Committee for IIOE. The stations are selected to
represent all 5° marsden squares for the entire Indian Ocean covering day/ night
and northeast/ southwest monsoons. 80% of each sample was sorted, keeping
20% as archive and these were sent to specialists in India and other countries.
Copepods were subsorted into 39 taxa (Table 3), of which 32 belong to the
order Calanoida, 3 Poecilostomatoida and 2 Cyclopoida. The orders Harpacticoida
and Siphonostomatoida were represented only by one taxon each.
The distribution of calanoid copepods is discussed based on the subsorted
taxa of the International Indian Ocean Expedition samples (Stephen et al., 1992).
Of the 32 calanoid taxa, only 17 groups are considered as significant components.
The family Eucalanidae is the most abundant group contributing to 31.09% of the
population. Genus
Pleuromamma and family Euchaetidae constituted 15% and
13% respectively. Among the more rare taxa, Tortanus is observed in the Bay of
Bengal, Pseudodiaptomidae are totally confined to the NW Indian Ocean and
Metridia is predominant near South Africa. Calanoides occurs very scattered, with
some large catches off Java and Oman, upwelling areas during the summer
monsoon. High densities of all the major groups were encountered in the equatorial
4
and northern Indian Ocean, especially in the productive areas (Stephen et al.,
1992).
4.2.2 Decapods
Decapods from all the 1548 samples were sorted into six categories namely
Sergestidae, Eryonidae, Phyllosoma larvae, Anomura postlarvae, Brachyura
postlarvae and others. These details along with total population of decapods are
shown in Table 4.
4.2.3 Fish larvae
Fish larvae are subsorted into 53 groups which include 46 families and 11
orders (Peter, 1982). In the Arabian Sea, 44 families are found and 39 families are
recorded from the Bay of Bengal (Table 5).
Larvae of Pleuronectiformes are subsorted into 4 families namely Bothidae,
Cynoglossidae, Soleidae and Pleuronectidae (Devi, 1986). However, population
count is given collectively for Cynoglossidae and Soleidae (Table 6).
5
4.3
Data at species level
4.3.1 Copepods
Population density for calanoid species identified from 342 subsorted
samples are given in Table 7. A total of nine species are identified from the Indian
Ocean. The species are Nannocalanus minor, Calanus australis, Undinula vulgaris,
Canthocalanus pauper, Neocalanus gracilis, N. robustior, N. tonsus, Calanoides
carinatus and Mesocalanus tenuicoruis (Stephen, 1998). C. pauper is the most
wide spread species followed by U. vulgaris and N. minor. Other species are
restricted to certain segments of the Indian Ocean.
4.3.2 Ostracods
32 species of ostracods are identified from 712 samples collected from the
northern Indian Ocean north of 10°S.
However, data for only 21 species are
available. The species belong to family Cypridinidae represented by two genera.
Family Halocyprididae is the most abundant group represented by 16 genera.
(George and Nair, 1980). Table
8 presents data for Cypridina dentata,
Euconchoecia chierchiae, E. aculeata, Halocypris brevirostris, Paraconchoecia
oblonga, P. echinata, P. elegens, P. discophora, P. procera, P. decipiens,
Conchoecetta acuminata, C. giesbrechti, Microconchoecia curta, Metaconchoecia
rotundata, Orthoconchoecia striola, Spinoecia porrecta, S. parthenoda, Conchoecia
magna, Pseudoconchoecia concentrica, Alacia alata and Conchoecilla daphnoides.
E. aculeata is the dominant species in the northern Indian Ocean. In the
Arabian Sea, C. dentata is the most abundant species.
4.3.3 Chaetognaths
Species level data for chaetognaths from all the standard hauls are
documented in Table 9. Total number of species found are 21 belonging to four
genera.
The species are Eukruhnia fowleri, Krohnitta pacifica, K. subtilis,
Pterosagitta draco, Sagitta bedoti, S. bipunctata, S. bombayensis, S. decipiens, S.
enflata, S. ferox, S. hexaptera, S. lyra, S. minima, S. neglecta, S. pacifica, S.
6
pulchra, S. regularis, S. robusta, S. serratodentata, S. tasmanica and S. zetesios
(Nair, 1977).
S. enflata is the most abundant species in the Indian Ocean. Other common
species are S. pacifica, P. draco, S. bipunctata and S. regularis. The
Somali-
Arabian coast is rich with regard to most of the species of chaetognaths with
maximum species diversity.
References
Currie, R.I. 1963. The Indian Ocean Standard net. Deep Sea Res. 10 (1-2) :27-32.
Devi, C.B.L. 1986. Studies on the flat fish (Heterosomata) larvae of the Indian
Ocean. Thesis submitted to University of Kerala for the Degree of Doctor of
Phiolosophy, 480 pp.
George, J. and Nair, V.R. 1980. Planktonic ostracods of the northern Indian Ocean.
Mahasagar – Bull. Natn. Inst. Oceanogr. 13 (1) : 29-44.
Hansen, V.Kr. 1966. The Indian Ocean Biological Centre. The Centre for sorting
plankton samples of the International Indian Ocean Expedition. Deep Sea Res. 13.
229-234.
IIOE, 1965-72. International Indian Ocean Expedition collected Reprints, Vols I-III,
UNESCO, Paris.
IIOE, 1969-73. IIOE Zooplankton Atlases, 1-5, and handbooks, 1-5. Indian Ocean
Biological Centre, National Institute of Oceanography, Cochin.
Nair, V.R., 1977. Chaetognaths of the Indian Ocean. Proc. Symp. Warm Water
Zoopl. Spl. Publ. UNESCO/ NIO, 168-195.
Nair, V.R., 2001. Zooplankton. 417-450. In : The Indian Ocean, a Perspective.
Volume 2. R. Sen Gupta and E. Desa (Eds.). Oxford and IBH Publishing Co Pvt.
Ltd, New Delhi, Calcutta.
NIO, 1997. Proceedings of the symposium on Warm Water Zooplankton, special
publication, UNESCO/ NIO, Goa, 722 pp.
Panikkar, N.K., 1963. The Indian Ocean Expedition. Curr. Sci., 32 (2) : 49-53.
Peter, K.J., 1982. Studies on some fish larvae of the Arabian Sea and Bay of
Bengal. Ph.D. Theseis, Univ. of Cochin (MS) : 349 pp.
7
Proceedings of the Symposium on Indian Ocean, 1969. No. 38. Part II. Bull. Natn.
Inst. India. 1037 pp.
Rao, T.S.S., Nair, V.R. and Madhupratap, M., 1981. Ecological considerations on
tropical zooplankton. Proc. Symp. Ecol. Anim. Popul. Zool. Surv. India. Part I, 1539.
Stephen, R., 1998. Geographical variation in the distribution of different calanoid
species in the Indian Ocean. Proc. 2nd International Conference, Pelagic
Biogeorgraphy. ICoPB II, 1995. IOC Workshop Report No. 142. 257-265.
Stephen, R., Saraladevi, K., Meenakshikunjamma, P.P., Gopalakrishnan, T.C. and
Saraswathy, M., 1992. Calanoid copepods of the International Indian Ocean
Expedition collections. In : Oceanography of the Indian Ocean. B.N. Desai (Ed.).
Oxford & IBH, New Delhi, 143-156.
Sverdrup, H.U., Johnson, M.W. and Fleming, R.H. 1942. The Oceans, their
physics, chemistry and general biology. Prentice-Hall, Inc., 1087pp.
The Biology of the Indian Ocean. 1973. B. Zeitzshcel and S.A. Gerlach (Eds.).
Springer Verlag, Berlin, Heidelberg. New York. 549 pp.
Wyrtki, K., 1973. Physical Oceanography of the Indian Ocean. In: The Biology of
the Indian Ocean. B. Zeitzschel, S.A. Gerlach (Eds) Springer Verlag, Berlin,
Heidelberg, New York. 18-36.
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