Genetic variation and population structure of krill (Euphausia superba) in the Atlantic sector of Antarctic waters and off the Antarctic peninsula

Polar Biology ◽  
1984 ◽  
Vol 3 (1) ◽  
pp. 19-28 ◽  
Author(s):  
R. Schneppenheim ◽  
C. M. MacDonald
Keyword(s):  
Population Structure ◽  
Genetic Variation ◽  
Antarctic Peninsula ◽  
Euphausia Superba ◽  
Atlantic Sector ◽  
Antarctic Waters ◽  
The Antarctic

Observations on moulting in Antarctic Krill (Euphausia superba Dana)

1982 ◽  
Vol 33 (1) ◽  
pp. 71 ◽  
Author(s):  
T Ikeda ◽  
P Dixon
Keyword(s):  
Phaeodactylum Tricornutum ◽  
Antarctic Krill ◽  
Dry Weight ◽  
Euphausia Superba ◽  
Dunaliella Tertiolecta ◽  
Antarctic Ocean ◽  
Fish Food ◽  
Antarctic Waters ◽  
The Antarctic ◽  
Antarctic Krill Euphausia Superba

Live E. superba were transported from Antarctic waters to a tropical laboratory where observations at the temperature of -0.5�C (0 to - 1.0�C), were made of intermoult period of specimens fed a mixture of microalgae (Dunaliella tertiolecta and Phaeodactylum tricornutum) or artificial pet fish food or starved. Mean intermoult period was 26.4-27.1 days for fed specimens and 29.6 days for starved specimens, with no relation to the size of specimens. The moult accounted for a loss of 2.63-4.35% of animal dry weight, which is equivalent to 1.1-1.8% of animal nitrogen or 1.4-2.3% of animal carbon. The contribution of moults to detritus in the Antarctic Ocean was estimated as 0.11 g C m-2 per year.

Stratigraphy of Antarctic late Cenozoic pectinid-bearing deposits

1998 ◽  
Vol 10 (2) ◽  
pp. 161-170 ◽  
Author(s):  
H.A. Jonkers
Keyword(s):  
Southern Ocean ◽  
Food Availability ◽  
Habitat Loss ◽  
Antarctic Peninsula ◽  
East Antarctica ◽  
Combined Effects ◽  
Late Cenozoic ◽  
Late Pliocene ◽  
Antarctic Waters ◽  
The Antarctic

Antarctic late Cenozoic pectinid-bearing sedimentary strata are chiefly confined to localities in the northern part of the Antarctic Peninsula, in the McMurdo Sound area, and Marine Plain, East Antarctica. Ages of these deposits range from Oligocene to Holocene. Chlamys-like scallops, which are absent from today's Southern Ocean, thrived in Antarctic waters during both glacial and interglacial episodes, but disappeared during the Late Pliocene. Their extinction is believed to result from the combined effects of increased carbonate solubility, habitat loss and limitations in food availability, associated with major cooling.

Length and age at maturity of Antarctic krill

1994 ◽  
Vol 6 (4) ◽  
pp. 479-482 ◽  
Author(s):  
V. Siegel ◽  
V. Loeb
Keyword(s):  
Antarctic Peninsula ◽  
Sexual Maturity ◽  
Antarctic Krill ◽  
Euphausia Superba ◽  
Knife Edge ◽  
Age At Maturity ◽  
Growth Season ◽  
The Third ◽  
Age Class ◽  
The Antarctic

Data from several summer research cruises in the Antarctic Peninsula region were analysed to calculate length (L50) and age at maturity for the Antarctic krill, Euphausia superba. Length at maturity L50 is defined as the length at which 50% of the krill stock attains sexual maturity. L50 values of 34.65–35.91 mm for female krill are the best estimates for the peak spawning season. Males attain sexual maturity later at L50 values of 43.35–43.71 mm. Length at maturity and length at first spawning are identical for krill. Comparisons with mean length-at-age data show that females mature in the third growth season (age class 2+), while males reach maturity in the fourth year (age class 3+). Both sexes show ‘knife-edge maturity’.

scholarly journals Population structure of Friesea grisea (Collembola, Neanuridae) in the Antarctic Peninsula and Victoria Land: evidence for local genetic differentiation of pre-Pleistocene origin

2010 ◽  
Vol 22 (6) ◽  
pp. 757-765 ◽  
Author(s):  
Giulia Torricelli ◽  
Francesco Frati ◽  
Peter Convey ◽  
Marco Telford ◽  
Antonio Carapelli
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Structure ◽  
Antarctic Peninsula ◽  
West Antarctica ◽  
Genetic Structure Of Populations ◽  
Victoria Land ◽  
Springtail Species ◽  
Ancestral Haplotypes ◽  
The Antarctic

AbstractFriesea grisea is the only springtail species currently described from both East (Victoria Land) and West Antarctica (Antarctic Peninsula), although levels of genetic divergence between the two regions suggest the possibility of cryptic species. Determining the genetic structure of populations in the two regions is necessary in order to compare the effects of the different environmental conditions in the two regions, the different evolutionary histories of their inhabitants, and for assessing any influence of latitude in each region on genetic diversity. We analysed sequences of the mitochondrial COX1 and ATP6 genes from a total of 111 individuals for 17 sites (nine on the Antarctic Peninsula and eight in Victoria Land), to assess levels of genetic diversity. Both regions have their own unique sets of haplotypes, differing by about 20% of their nucleotide sequences. A similar number of haplotypes was found in the two regions, and within each we found two groups of populations sharing no haplotypes. In the Antarctic Peninsula, two, presumably ancestral, haplotypes are dominant in frequency. In Victoria Land, the Cape Hallett population showed a distinct set of haplotypes, genetically different from the southernmost populations, suggesting differentiation on pre-Pleistocene timescales.

Sign in / Sign up

Export Citation Format

Share Document