The Patagonian toothfish fishery in Falkland Islands’ waters

Abstract

Abstract This paper examines and provides updated information on the status of toothfish stocks within Falkland Islands conservation zones and also provides a historical perspective of the fishery. The Patagonian toothfish has been taken as a bycatch since the trawl fishery was established in the Falkland Islands. However, specialised exploitation of the Patagonian toothfish started with the opening of the Falkland Islands Outer Conservation Zone (FOCZ) in 1994 when demersal longliners started to target this species at depths of greater than 600 m. When compared to trawlers, analysis showed that longline catches were higher in weight but not numbers. Generally longline catches comprised fish of greater than their length at 50% maturity whereas this situation is rare in catches taken by trawlers. Longliner CPUE peaked in the first year of the fishery and gradually declined until 2000–2001 after which it remained relatively stable with a small increase in 2003–2004. The latter is attributed to a strong year class born in 1994. Toothfish recruitment in the Falkland Islands was found to be very variable. Strong year classes seem to occur every 4–5 years. The mean size of toothfish has decreased since the onset of the longline fishery. This decrease mainly occurred between 1994 and 1999, since then the size of toothfish in catches has remained relatively stable. Fox and Schaefer production models show a strong decline in biomass with the current stock size at about 50% of its unexploited state. It is concluded that the fishery is still just within its limits of sustainable use.