Preliminary study on reproduction in Champsocephalus gunnari from Subarea 48.3, Dr Eduardo Holmberg survey, February/March 1994

A preliminary histological analysis on the ovarian development in Champsocephalus gunnari was carried out. Six stages of oocytary development were identified and are similar to those described for other species. A gonad maturation scale was elaborated and adapted to the macroscopic scale commonly used. Oocytary resorption processes were observed during ovarian maturation. In some cases the ovaries presented few atretic oocytes ; in others a generalized regression was found. In the southwest portion of the South Georgia shelf, 50 % of the ovaries exhibited a pre-reproductive regression stage similar to that reported for the same species in the 1991 summer season.