Bottom trawl surveys were conducted by the United States Antarctic Marine Living Resources program in two major regions of the South Shetland Islands: Elephant Island and the lower South Shetland Islands from King George Island to Livingston Island. Information on species composition, catch levels, size composition, and condition are described and compared between the two regions. Maturity ogives were constructed for five species of finfish: Champsocephalus gunnari, Gobionotothen gibberifrons, Chaenocephalus aceratus, Chionodraco rastrospinosus, and Lepidonotothen squamifrons. Estimates of length at sexual maturity and length at first spawning are computed and compared with previous estimates and other populations.
Abstract:
Bathymetric maps of two major areas within the South Shetland Islands were generated using several integrated bathymetric databases. These areas comprise the lower South Shetland Island chain from King George Island to Smith Island, and the region around Elephant Island. From the integrated data sets, areas of seabed within the 500 m isobath for six levels of depth strata (0-50 m, 51 - 100 m, 101-200 m, 201 -300 m, 301-400m, 401-500 m) were computed. Areas were calculated based on true surface area of seabed incorporating seafloor slope
Abstract:
The absolute and relative fecundity of Patagonian toothfish inhabiting areas of South Georgia Island and Shag Rocks were studied. The absolute individual fecundity of toothfish in relation to the size of specimens ranged from 56,3 to 567.5 thousands of eggs, averaging 152,9 thousands of eggs. Values of relative individual fecundity of toothfish varied from 4,1 to 13,0 thousands of eggs (averaging 8.19 ± 1,73 thousands of eggs ) per 1 kg of fish body weight. Our studies and the analysis of data published previously indicate, that Patagonian toothfish similar to the most of Notothenioids characterized by large eggs can be included in the fish group having a level of absolute fecundity and a low value of relative fecundity.