Summary
Zooplankton was sampled with RMT (1+8) gear on a synoptic grid of stations centred on South Georgia during the austral summer (November/December 1981) and winter (July/August 1983). This initial paper compares zooplankton biomass, vertical distribution and species composition from RMT 1 catches in the oceanic portion of the grid (water depth greater than 2000 m) during the two surveys. In the winter survey, mean zooplankton biomass within the top 1000 m of the water column was 68% of its summer level. This drop was largely due to a decrease in abundance of krill (Euphausia superba), although biomass of copepods and remaining zooplankton also decreased. Copepods averaged 48% of total biomass in summer and winter, but outnumbered all other taxa put together by a factor of 10. Antarctic epipelagic species predominated around the island in the summer survey but tended to be replaced by sub-Antarctic or cosmopolitan species during the winter survey. The majority of zooplankton also showed a downwards seasonal migration out of the top 250 m layer in winter. However, several epipelagic species, including E. superba, did not migrate, and these tended to have the largest summer-winter differences in overall abundance. These trends were attributed to variation in the position of the Polar Front, which lay north of the island during the summer survey but lay across the survey area in winter, resulting in a greater influence of sub-Antarctic water and the displacement of Antarctic species.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Amos AF (1984) Distribution of krill (Euphausia superba) and the hydrography of the Southern Ocean: large-scale processes. J Crust Res 4:306–329
Andrews KJH (1966) The distribution and life-history of Calanoides acutus (Giesbrecht). Discovery Rep 34:1–116
Baker AdeC (1959) Distribution and life-history of Euphausia triacantha Holt and Tattersall. Discovery Rep 29:309–340
Barnard JL (1969) The families and genera of marine gammaridean amphipoda. US Nat Mus Bull 271:1–535
Brinton E (1985) The oceanographic structure of the eastern Scotia Sea. III. Distributions of euphausiid species and their developmental stages in 1981 in relation to hydrography. Deep-Sea Res 32: 1153–1180
Foxton P (1956) The distribution of the standing crop of zooplankton in the Southern Ocean. Discovery Rep 28:191–236
Gordon AL (1967) Structure of Antarctic waters between 20°W and 170°W. Antarct Map Folio Ser 6, 10 pp
Gordon AL, Goldberg RD (1970) Circumpolar characteristics of Antarctic waters. Antarct Map Folio Ser 13, 10 pp
Griffiths FB, Brown GH, Reid DD, Parker RR (1984) Estimation of sample zooplankton abundance from Folsom Splitter subsamples. J Plankton Res 6:721–731
Hardy AC, Gunther ER (1935) The plankton of the South Georgia whaling grounds and adjacent waters, 1926–1927. Discovery Rep 11:1–456
Heron GA (1977) Twenty-six species of Oncaeidae (Copepoda: Cyclopoida) from the Southwest Pacific-Antarctic area. In: Pawson DL (ed) Biology of Antarctic Seas 6. Antarct Res Ser 26:37–96
Heywood RB, Everson I, Priddle J (1985) The absence of krill from the South Georgia zone winter 1983. Deep-Sea Res 32:369–378
Hopkins TL (1971) Zooplankton standing crop in the Pacific sector of the Antarctic. In: Llano GW, Wallen IE (eds) Biology of the Antarctic Seas 4. Am Geophys Union 17:347–362
John DD (1936) The southern species of the genus Euphausia. Discovery Rep 14:193–324
Kane JE (1966) The distribution of Parathemisto gaudichaudii (Guer), with observations on its life-history in the 0° to 20° sector of the Southern Ocean. Discovery Rep 34:163–198
Legeckis R (1977) Ocean polar front in the Drake Passage — satellite observations during 1976. Deep-Sea Res 24:701–704
Mackintosh NA (1934) Distribution of the macroplankton in the Atlantic Sector of the Antarctic. Discovery Rep 9:65–160
Mackintosh NA (1937) The seasonal circulation of the Antarctic macroplankton. Discovery Rep 16:365–412
Marin V (1987) The oceanographic structure of the eastern Scotia Sea. Part IV. Distribution of copepod species in relation to hydrography in 1981. Deep-Sea Res 34:105–121
Marr JWS (1962) The natural history and geography of the Antarctic krill (Euphausia superba Dana). Discovery Rep 32:33–464
Mauchline J (1980) The biology of mysids and euphausids. Adv Mar Biol 18:373–595
Nowlin WD, Klinck JM (1986) The physics of the Antarctic Circumpolar Current. Rev Geophys 24:469–491
Ommanney FD (1936) Rhincalanus gigas (Brady), a copepod of the southern macroplankton. Discovery Rep 13:277–384
Park T (1978) Calanoid copepods belonging to the families Aetideidae and Euchaetidae from Antarctic and Subantarctic waters. In: Pawson DL (ed) Biology of Antarctic Seas 7. Antarct Res Ser 27:91–290
Park T (1980) Calanoid copepods of the genus Scolecithricella from Antarctic and Subantarctic waters. In: Kornicker LS (ed) Biology of Antarctic Seas 4. Antarct Res Ser 31:25–79
Pommeranz T, Herrmann C, Kuhn C (1983) Mouth angles of the Rectangular Midwater Trawl (RMT 1+8) during paying out and hauling. Meeresforschung 29:267–274
Priddle J, Heywood RB, Theriot E (1986) Some environmental factors influencing phytoplankton in the Southern Ocean around South Georgia. Polar Biol 5:65–79
Priddle J, Croxall JP, Everson I, Heywood RB, Murphy EJ, Prince PA, Sear CB (in press) Large-scale fluctuations in distribution and abundance of krill — a discussion of possible causes. In: Sahrhage (ed) Antarctic ocean and resources variability. Springer, Berlin Heidelberg New York
Roe HSJ, Shale DM (1979) A new multiple rectangular midwater trawl (RMT1+8) and some modifications to the Institute of Oceanographic Science's RMT 1+8. Mar Biol 50:283–288
Tebble N (1960) The distribution of pelagic polychaetes in the South Atlantic Ocean. Discovery Rep 30:161–300
Tranter DJ (1982) Interlinking of physical and biological processes in the Antarctic Ocean. Oceanogr Mar Biol Ann Rev 20:11–35
Vervoort W (1957) Copepods from Antarctic and Sub-Antarctic plankton samples. Rep BANZ Antarct Res Exp, Ser B 3:1–160
Vervoort W (1965) Notes on the biogeography and ecology of free-living marine copepoda. In: Oye Pvan, Mieghem Jvan (eds) Biogeography and ecology in Antarctica. Monogr Biol, vol 15. Junk, The Hague, pp 381–401
Vladimirskaya YeV (1975) Distribution of zooplankton in Scotia Sea in fall and winter. Oceanology 15:359–362
Voronina NM (1970) Seasonal cycles of some common Antarctic copepod species. In: Holdgate MW (ed) Antarctic ecology, vol 1. Academic Press, London, pp 162–172
Voronina NM (1972) Vertical structure of a pelagic community in the Antarctic. Oceanology 12:415–420
Voronina NM, Valdimirskaya YeV, Zmiyevskaya MI (1978) Seasonal variations in the age composition and vertical distribution of common zooplankton species in the Southern Ocean. Oceanology 18:335–338
Voronina NM, Menshutkin VV, Tseytlin VB (1979) Mathematical simulation of the space-time distribution and age structure of an Antarctic copepod population. Oceanology 19:76–81
Voronina NM, Menshutkin VV, Tseytlin VB (1980) Model investigations of the annual population cycle of the abundant copepod species Rhincalanus gigas and estimate of its production in the Antarctic. Oceanology 20:709–713
Whitworth T (1980) Zonation and geostrophic flow of the Antarctic circumpolar current at Drake Passage. Deep-Sea Res 27:497–507
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Atkinson, A., Peck, J.M. A summer-winter comparison of zooplankton in the oceanic area Around South Georgia. Polar Biol 8, 463–473 (1988). https://doi.org/10.1007/BF00264723
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00264723