Location and intensity of the Soviet krill fishery in the Elephant Island area (South Shetland Islands), 1988/89
This paper analyses fine-scale data from the Soviet krill fishery off Elephant Island (Subarea 48.1) between 59°-62°S and 53°-57°W during the period from 21 November 1988 to 25 March 1989. Although the total catch of the USSR in this season reached a maximum, for the last nine seasons the total fishing intensity by the USSR around Elephant Island has been low. In 1988/89 only one standard fishing vessel operated in the area over 40% of the time. The highest catch-per-unit-effort was observed in January 1989 (7.7 tonnes per hour of trawling on average), and the lowest in November 1988 (3.5 tonnes per hour of trawling on average). Fishing strategy in the Elephant Island area conforms to the following simple pattern: (i) vessels enter the island near-shore zone (north of Elephant Island) and start searching for krill concentrations; (ii) krill concentrations are fished and followed as they drift from the island with the current; and (iii) vessels return to position (i) when aggregations are dispersed or lost due to storms and other factors. The velocity of the northeast drift of krill concentrations, calculated on the basis of vessel relocation, was from 9.7 to 11.1 km/day (11 to 13 cm/sec). An analysis of the location of fishing grounds by five-day periods showed that the areas in which the fleet operated overlap a minor part of the foraging zones of krill predators. Based on this, and taking into account the low fishing intensity, it was concluded that the current krill fishery does not significantly affect krill-eating seals and birds.