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.