An age-length key was prepared for Champsocephalus gunnari from the Subarea 48.3, based on the readings of otoliths randomly collected during the R/V Holmberg survey in Feb/Mar 1994. Small and medium sized fish (total length 12-33 cm) constituted the bulk of the samples (93%), while larger specimens (>33 cm) were scarce. At South Georgia, fish of age groups 1-4 were truly represented; at Shag Rocks, a large concentration of fish belonging to age groups 2 (90%) and 3 (10%) was found. The length weighted distribution of all the fish sampled in the Subarea 48.3 showed good correspondence between modes and, the mean lengths of age groups 1-2. Such correspondence was also obtained for age group 3 when the data from South Georgia were analyzed separately. Mean length at age presented here fall in the range of available results from previous surveys in the South Georgia region.
Age-length key for Champsocephalus gunnari from Subarea 48.3, Dr Eduardo Holmberg survey, February/March 1994
Numéro du document:
WG-FSA-94/11
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