Krill Fishery

The third fishery that currently operates in South Georgia waters targets Antarctic krill (Euphausia superba) with pelagic trawl nets. Krill are small (up to 60 mm long) shrimp like creatures that can be found in huge aggregations in Antarctic and South Georgia waters. Krill are important in the pelagic food-web of the Southern Ocean, linking primary production (plankton) to vertebrate predators (fish, seabirds and marine mammals).

 

Krill

Background

Vessels from Japan and the former Soviet Union began to fish for krill at South Georgia, and around Antarctica, in the 1970s. Vessels from other nations quickly joined the fishery, which peaked at over 500,000 tonnes in the early 1980s. Concern over the rapid expansion of the krill fishery and the potential impact on non-target species led to the establishment of CCAMLR in 1982. Catches dipped in the 1980s, largely due to the discovery of high fluoride levels in the krill exoskeleton and the associated processing problems. Catches dropped again in the 1990s due to the break-up of the former Soviet Union. In recent years, catches are currently around 200,000 tonnes for the wider Scotia Sea. Since the early 1990s, the average annual catch within South Georgia waters has been 25,000 tonnes but this can vary widely from one year to the next. The variations are largely down to environmental conditions, fluctuations in sea ice coverage affect krill recruitment and vessels will fish further south when sea ice conditions allow. For this reason, the South Georgia fishery was regarded as a winter fishery, when conditions are unfavourable further south. The MPA order (2013) introduced a formal seasonal closure between November 1st and March 31st this reduces the risk of competition between the fishery and krill dependent predators, particularly the land-based predators that are constrained in their foraging ranges during the breeding season.

Krill are caught in pelagic nets and there is little bycatch. Fur seals have occasionally been caught in the past, but now escape panels are mandatory and no fur seals have been reported caught since 2003. In recent years, continuous trawl gear has been developed, which continuously returns the catch from the net to the vessel for processing. This is highly efficient and can result in a single vessel catching 800 tonnes per day. Simultaneously, new processing technology has been developed to extract krill oil, which is used in the health food industry.

Krill trawler in Cumberland Bay.

Krill trawler in Cumberland Bay.