[Personnel: Last_Name='CONNELL', First_Name='DAVE']
Abundance, Life-cycle and Potential Productivity of 'Euphausia superba' and its Relationship With Other Zooplankton in Prydz Bay, AntarcticaEntry ID: ASAC_229
Abstract: Metadata record for data from ASAC Project 229
See the link below for public details on this project.
From the abstracts of some of the referenced papers:
In January 1985 a net sampling survey was carried out on the distribution and abundance of euphausiid larvae in the Prydz Bay region. Euphausia superba occurred in low abundance, probably due to sampling preceding the main spawning ... period. Thysanoessa macrura occurred throughout the study area in consistently high abundance. Euphausia crystallorophias as marginally more abundant within its restricted range. Distinct north-south variations in larval age and development stages of T. macrura were observed indicating regional differences in spawning. Euphausia frigida was mainly confined to the upper 200 m of the Antarctic Circumpolar Current. Larvae originating on the shelf moved rapidly west in the East Wind drift. E. crystallorophias had the same westward dispersion, but some larvae appeared to return eastward via the Prydz Bay Gyre and remain in the region. The data indicate that most E. superba larvae, providing they survive injurious cold temperature and food deprivation, will leave the area, suggests that Prydz Bay krill may not be a self sustaining stock.
This paper presents results of net sampling carried out in four marine science cruises between 1981 and 1985, in the Prydz Bay region of Antarctica by the Australian Antarctic Division. Krill exhibited a patchy distribution and overall low abundance. The majority of sampling sites in January 1985 returned no post-larval krill or densities of less than 1 individual per 1000 cubic metres. The estimated mean abundance of E. superba in January 1985 was 6 indivduals or 2 g (wet wt.) per 1000 cubic metres integrated for the upper 200m of the water column which represented 3.4% of the total zooplankton biomass. No more than five years-groups, including the larvae, were observed in Prydz Bay, with mean lengths of groups 1+, 2+, 3+ and 4+ being 24, 38, 46 and 53 mm (standard 1), respectively in the middle of January. A high proportion of naupliar stages observed in January 1985 indicated that spawning in Prydz Bay begins in January and examination of adult maturation showed that the spawning continues at least to March.
Sixty female Antarctic krill (Euphausia superba Dana) spawned in shipboard experiments and the interval between egg-laying and ecdysis was noted. The number of eggs laid per female ranged from 263-3662, most females produced only one batch of eggs before moulting, and the post spawn ovaries of all females contained few, if any, mature oocytes. As reported in other studies, the total number of eggs produced per female was not well correlated with body size. Females appeared to spawn at all times during the moulting cycle and although no diurnal rhythm in spawning was observed, moulting occurred mainly at night-time despite the animals being kept in near-constant darkness. No evidence of synchronous moulting was detected.
Data from this project were collected on five Antarctic voyages:
HIMS - Heard Island Marine Science - 1990-05-04 - 1990-07-01
AAMBER II - Australian Antarctic Marine Biological Ecosystem Research II - 1991-01-3 - 1991-03-19
FISHOG - Fish and Oceanography - 1992-01-09 - 1992-03-27
KROCK - Krill and Rocks - 1993-01-05 - 1993-03-09
BROKE - Baseline Research on Oceanography, Krill and the Environment - 1996-01-02 - 1996-03-31
All data are available in the download file.
(Click for Interactive Map)
Start Date: 1990-05-04Stop Date: 1996-03-31
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ARTHROPODS > CRUSTACEANS
BIOSPHERE > AQUATIC ECOSYSTEMS > PLANKTON > ZOOPLANKTON
BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > SPECIES LIFE HISTORY
BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > POPULATION DYNAMICS
BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > SURVIVAL RATES
Data Set Progress
Phone: +64 7 856 7026
Fax: +64 7 856 0151
Email: v.cummings at niwa.co.nz
NIWA PO Box 11-115
Country: New Zealand
Role: DIF AUTHOR
Phone: +64 3 358 0200
Fax: +64 3 358 0211
Email: s.gordon at antarcticanz.govt.nz
Antarctica New Zealand Private Bag 4745
Country: New Zealand
Cummings, V.J. 2003. Assessing biodiversity on the Antarctic sea floor. Water and atmosphere 11(3): 10-12, 2003.
Thrush, S.F., Hewitt, J.E., Cummings, V.J., Norkko, A. And Chiantore, M. 2010. ß-Diversity and species accumulation in Antarctic coastal benthos: Influence of habitat, distance and productivity on ecological connectivity. PLOS One 5(7): e11899 doi:10.1371/journal.pone.0011899
Cummings, V. Thrush, S. Norkko, A. Andrew, N. Hewitt, J. Funnell, G. Schwarz, A.-M. Accounting for local scale variability in benthos: implications for future assessments of latitudinal trends in the coastal Ross Sea. Antarctic science 18(4): 633-644, 2006.
Norkko, J. Indicators of short-term growth in bivalves: detecting environmental change across ecological scales. Ph.D., University of Auckland : . 2005.
Norkko, A. Thrush, S.F. Cummings, V.J. Gibbs, M.M. Andrew, N.L. Norkko, J. Schwarz, A-M. Trophic structure of coastal Antarctic food webs associated with changes in sea ice and food supply. Ecology 88: 2810-2820, 2007.
Schwarz, A.-M. 2003. Life in the dark: plant growth beneath the sea ice. Water and atmosphere 11(3): 14-15, 2003.
Norkko, J. Norkko, A. Thrush, S.F. Cummings, V.J. Detecting growth under environmental extremes: Spatial and temporal patterns in nucleic acid ratios in two Antarctic bivalves. Journal of experimental marine biology and ecology 326: 144-156, 2005.
Creation and Review Dates
DIF Creation Date: 2005-10-11
Last DIF Revision Date: 2010-12-08