Kock, K.-H. (1985), Estimates of fish stock biomass around South Georgia in January/February 1985

Catch data from a bottom trawl survey in January/February 1985 have been used to estimate stock sizes of the commercially exploited Notothenia rossii, N. guntheri, N. gibberifrons, Dissostichus eleginoides, Champsocephalus gunnari, Chaenocephalus aceratus and Pseudochaenichthys georgianus around South Georgia. Due to the small data base and the scarcity of comparative information the state of N. guntheri and D. eleginoides stocks is difficult to assess. The by-catch species N. gibberifrons, Ch. aceratus and Ps. georgianus have been considerably affected by the fishery. Stock sizes of N. gibberifrons and Ps. georgianus were at a level of about 25 – 40% of that of the pristine state. The stocks most greatly affected by fishing are still N. rossii and C. gunnari. Biomass estimates indicate a reduction in stock size to 10 – 20% of that estimated before the onset of heavy fishing. In C. gunnari the fishery is dependant on the abundance of the recruiting year class. Conservation measures adopted by CCAMLR in 1984 are discussed. Their effect on a recovery of the stocks seems, however, doubtful.

Kock, K.-H. (1985), Preliminary results of investigations of the Federal Republic of Germany on Notothenia rossii marmorata (Fischer, 1885) in January/February 1985

A bottom trawl survey carried out by FRV "Walther Hervig" in January/February 1985 was used to collect further basic data needed for stock assessment purposes, to assess the actual size of Notothenia rossii around South Georgia and Elephant Island and the extent to which the measures adopted by CCAMLR to rebuild the stock around South Georgia might be successful. Although reported catches in recent years have been low, N. rossii around South Georgia is still largely affected by the fishery. Stock size is probably still less than 10% of the pristine stock, Mean length in the catches has only slightly increased since 1981/82 and is still close to length at sexual maturity. The major part of the population consisted of age classes V – VIII. It seems doubtful if the conservation measures adopted in 1984 will really help to rebuild the stock around South Georgia.

South Africa (1985), Research currently being undertaken by the Republic of South Africa on "dependent and related species" within the Antarctic marine ecosystem

Selected components of the biological sciences programme are described. The primary objective of the studies being undertaken is to improve our understanding of the ecology of important predators (especially seals and seabirds) and their prey (especially krill and squid) in the Antarctic, and closely related marine ecosystems.

Lubimova, T.G. (1985), Results of Soviet investigations of the distribution and ecology of pelagic squids (Oegopsida) in the Southern Ocean

The USSR has carried out a long-term investigation of the distribution and ecology of pelagic squids (Oegopsida) in the Southern Ocean. In 1965–1977 a total of 326 squid specimens were collected at 124 stations with sampling by midwater nets. 125 specimens of that total were identified as Brachioteuthis riisei. In recent years (1978-1984) the collection was increased by two or three dozen specimens mostly identified as the little-studied Alluroteuthis antarcticus (family Neuleuthidae). 14 species of squid are considered to inhabit permanently the Southern Ocean. They belong to 9 families (13 genera). The pelagic squids are very seldom caught by fishing nets in Antarctic waters and data on squid beaks taken from sperm whale stomachs were also considered.

Up-to-date descriptions of all fourteen species are suggested. Where data are available the description includes geographical distribution, habitat, size, food diet and position of a species in a food web. Such description is also suggested for M. hamiltoni, the data on which come only from beaks found in sperm whale stomachs. All species are divided into three major groups in accordance with their habitats: tropico-subtropical, natal and Antarctic types.

In view of the absence of squid beaks in the bottom sediments in the Antarctic, two hypotheses are suggested: all squids migrate to the Antarctic in the summer seasons from the sub-tropical and notal areas, or the abundance of the true meso- and bathypelagic squids is very low.

It is proposed to concentrate future research on squids in the waters of high bioproductivity south of 60°S.

Mizroch, S.A. et. al (1985), Preliminary atlas of Balaenopterid whale distribution in the Southern Ocean based on pelagic catch data

A series of 57 computer-generated maps is presented, depicting the locations of pelagic catches of Balaenopterid whales by month between 1931/32–1979/80. Two sets of maps were produced. The first series contains 24 maps of catches by species by month, and the second consists of 30 maps of catches of fin whales for each season from 1952/53–1961/62 for January, February and March, plus three summary maps of fin whales catches for the years 1952/53–1961/62 combined, for each of the three months.