New data on spawning, hatching and growth of Champsocephalus gunnari on the shelf of the Kerguelen Islands
Combined studies on the inner and outer northeastern part of the Kerguelen shelf during the 1989/90 to 1993/94 period provide new information on the stock of Champsocephalus gunnari. A quarterly program of ichthyoplanktonic and bottom trawl surveys over the inner shelf has enabled a new cohort of fish to be identified each year. However, annual variations in abundance have been observed. During the sampling period the 1988 cohort was dominant on the outer shelf. The three-year cycle observed previously seems to be related to the maturation stage of each current cohort and the relative abundance of spawners-at-age during each winter spawning period. Only once have spawners been observed in large numbers on the inner shelf: during the winter of 1991/92. These fish were the first of the 1988 cohort to spawn.