CCAMLR

This study was based on the data from the ichthyoplankton survey made in March-April 1989 by R/V "Vozrozhdenie" in the subtropical frontal zone over the South Atlantic ridge crest between 38°30’ - 45°S. and 15° - 20°W. Larvae were collected with BONGO and JUDAY nets in oblique arid vertical hauls at 500 - 0m. The method of delta-distribution of random values (Aitchison, Brown, 1957; Pennington, 1983) was used to count the larvae. The data obtained was taken to estimate the recruitment biomass (fish aged up to 1 year) in this species for the area of 87750 square miles studied. The abundance of larvae in this area was 4.3 x 10 ind., while the biomass of one year old fish obtained was 10750 tons. A whole chain of similar reproductive grounds is assumed to exist in the notal zone of the Atlantic and other sectors of the South Ocean to be able to sustain a large biomass of E. carlsbergi in waters of the south po1ar frontal zone.

Shipboard tracking study of breeding chinstrap penguins (Pygoscelis antarctica) and Antarctic fur seals (Arctocephalus gazella ) at Seal Island were conducted to identify and evaluate their foraging areas in late December 1994 (Leg I) and late January 1995 (Leg II). Leg I and Leg II corresponded to the incubation and guard period, respectively, for chinstrap penguins ; penguins were divided into diurnal and overnight foragers during Leg II. Highest krill (Euphausia superba) densities regularly occurred on the shelf north of Seal Island. However, all predators except diurnal foraging penguins went northward beyond the shelf, and foraged in offshore region during Leg I and on slope during Leg II. The diurnal foraging penguins alone fed on the shelf. The following advantages are considered for feeding in the offshore/slope regions over on the shelf: (1) krill were present near the surface throughout the day so that only shallow diving was required to catch krill even in the day time; (2) krill tend to be larger in size; and (3) Myctophid fish occurred within the predators' maximum diving range at night. Considering that overnight foraging was always made in the offshore/slope regions, (3) is regarded as the most important factor making the predators except diurnal foragers choose the offshore/slope regions (less abundant areas for krill) over the shelf region (more abundant areas for krill).