Length-age composition of the Patagonian toothfish, Dissostichus eleginoides, from the Kerguelen Island area

Results of length-age composition studies of the Patagonian toothfish, Dissostichus eleginoides, from various fishing grounds of the shelf and continental slope areas of the Kerguelen Islands are presented and discussed in the paper. Detailed results of these studies are compiled in tables such as age-length keys, mean fish length by age, length and age frequency distributions in catches. Soviet vessels had first carded out fishery for the species in the 1984/85 season. Fishing grounds during this period were located in the west shelf area (48°30’ - 49°30’S and 66°50’ - 67°20’E). Total catch was about 6.7 x 103 tonnes. Length composition of catches taken within 300 - 500 m depth range did not fluctuate considerably, mean fish length was 76.0 - 86.6 cm. Fish of two to 14 years old age groups were most abundant in catches, mean age was 8.2 - 9.8 years. In the 1991/92 season fishing for the species was concentrated in the north shelf area (47°10’ - 47°30’S and 66°50’ - 67°20’E). Total catch was about 5.2 x 103 tonnes. In other seasons between 1984 and 1992 catches of the species was taken only occasionally and annual catches were from 0.5 to 3.1 x 103 tonnes. Mean length of fish taken at 300 - 500 m depth was 58.1 cm, mean age was 5.8 years. Mean length of fish taken at 540 - 600 m depth was 85.8, mean age was 9.7 years. Results presented in the paper are in agreement with results of other studies conducted in the past by French and Russian scientists.