The stocks of Notothenia rossii marmorata and Champsocephalus gunnari in the South Georgia area are assessed using USSR age sample data and recent biomass estimates from surveys by the FRG. These data Indicate that the stock of N. rossii in 1985 was about 2.5% of its pre-exploitation biomass, while the stock of Champsocephalus gunnari has fluctuated greatly with no obvious trend.
Abstract:
Preliminary results of a bottom trawl survey around Elephant Island carried out fromboard RV "Polarstern" in May/June 1986 give some insight into spawning activities and changes in length compositions and biomass estimates in Notothenia rossii, N. gibberifrons, N. coriiceps neglecta,, Champsocephalus gunnari, Chaenocephalus aceratus and Chionodraco rastrospinosus. Spawning was only observed in N. c. neglecta, whereas very little or no spawning was evident for N. rossii, C. gunnari and Ch. aceratus. Peak spawning of N. c. neglecta is limited to only a few weeks. In populations of C. gunnari and Ch. rastrospinosus no major changes took place from February 1985 to May/June 1986.
