On the problem of icefish (Champsocephalus gunnari) vertical migration on the South Georgia shelf

The results are presented of studying icefish vertical migration based on the data of R/V cruises during the seasons of 1982-83, 1983-84 and 1986-87, when this species was highly abundant on the South Georgia shelf. It is revealed that at day time the fish distributes near the bottom and the maximum catches were available at the middle of the light hours of the day. At twilight the fish concentrations migrate into the water column and the catches greatly decrease. The direct observations of icefish vertical migrations provided by means of hydroacoustic equipment are presented.