Evaluation for SOE indicator 33 - Annual catch in tonnes of marine species harvested in Antarctic and subantarctic waters

Harvesting of Antarctic and subantarctic marine living resources began in the 1969/70 season when there was no effective jurisdiction or control over fishing. Very high catches of Notothenia rossii were taken around South Georgia and the Kerguelen Islands, but stocks and catches declined rapidly so that by 1973 catches had stabilised at about 20,000 tonnes per annum from an initial peak of nearly 400,000 tonnes. In the late 1970s catches reached about 50,000 tonnes in a couple of seasons when areas around the South Orkney Islands and South Shetland Islands were exploited, but again catches at those levels were not sustained.

Following the pulse of fishing on N. rossii, other species were targeted by the trawlers. The principal species were Lepidonotothen squamifrons and Champsocephalus gunnari (mostly around the Kerguelen Islands and South Georgia but also with significant amounts from the South Orkney and South Shetland Islands). Other species such as Gobionotothen gibberifrons, Chaenocephalus aceratus and Chaenodraco wilsoni were taken as bycatch or were targeted in conjunction with the C. gunnari fishery in the South Georgia, South Orkney Islands and South Shetland Islands areas.

Around 1980 two significant events occurred that had a profound effect on fishing practices. One was the establishment of 200 nautical mile Exclusive Economic Zones (EEZs) around the Kerguelen and Crozet Islands (France), Marion and Prince Edward Islands (South Africa) and Heard and McDonald Islands (Australia). This excluded most fishing vessels from some of the most productive fishing grounds, especially around the Kerguelen Islands, and allowed relevant national authorities to institute management arrangements. The second was the establishment of the international Convention for the Conservation of Antarctic Marine Living Resources and a Commission (both with the acronym CCAMLR) in 1980 to manage harvesting in the Convention area, which stretches from the Antarctic coast northwards to approximately the position of the Polar Front and thus covers almost all the Antarctic and subantarctic fisheries.

During the 1980s the catches of most fish species generally declined as a result of declining stocks and management measures imposed by CCAMLR and national authorities. Some of the first CCAMLR conservation measures were to prohibit directed fishing on N. rossii. Other conservation measures during the 1980s restricted catches of G. gibberifrons, C. aceratus and other bycatch species, and later required the taking of C. gunnari by midwater trawl only, thus largely removing the problem of bycatch. France likewise terminated the fisheries for N. rossii and L. squamifrons within the Kerguelen EEZ. By contrast, fisheries for some other species started or increased markedly during this period. Catches of Patagonotothen brevicauda and Lanternfish reached high levels, but ceased shortly after 1990 after the breakup of the Soviet Union, which was the principal fishing nation for these species. The directed fishery for Dissostichus eleginoides started in 1985 and catches from South Georgia, Kerguelen Island, Heard Island, Marion & Prince Edward Islands and Crozet Islands have risen steadily to their present levels. Unlike other fisheries, this species is mostly caught by longline. C. gunnari continued to be taken during this period, but the abundance and therefore catches of this species varied widely from year to year. This fish has a much shorter life history than most other Antarctic species, and the population at any one time is mostly composed of one or two abundant year classes. The success of the fishery depends on whether the abundant year classes are available to the fishery.

Since 1992 only three species have supported significant fisheries: Dissostichus mawsoni, D. eleginoides and C. gunnari. Of these, the fishery for D. eleginoides was by far the most important, both in terms of tonnage and value. The fishery responded to strong demand from the United States and Japan in particular for premium table fish, and prices have generally been high. This has led to a serious problem with illegal, unregulated and unreported (IUU) fishing for this species. While the status and trends if the stocks of species that support the established legal fisheries at South Georgia, Kerguelen and Heard Island are sufficiently well-known to allow the setting of conservative total allowable catches (TACs) with some confidence, the activities of the IUU vessels have the potential to undermine these assessments. Perhaps more seriously, IUU vessels are thought to have heavily fished areas where little or no legal fishing has occurred, in particular Ob' and Lena Banks, Crozet Islands, Marion and Prince Edward Islands and probably to a lesser extent Elan and BANZARE Banks. Stocks of D. eleginoides in at least some of these areas are likely to have been significantly depleted, although without research or fishery data from these areas, the extent of the depletion is difficult to assess. A number of measures have been instituted to combat the IUU problem. Several IUU vessels have been arrested and successfully prosecuted by a number of national authorities, and a Catch Documentation Scheme has been introduced by CCAMLR in an attempt to ensure that only legally caught fish is sold on to the market.

The value of toothfish products has stimulated the exploration of new areas closer to the Antarctic Continent, within the sea-ice zone. Since 1998 a longline fishery has developed for Antarctic Toothfish, Dissostichus mawsoni in the Ross Sea area. While this is still classified as an exploratory fishery, research and fishery data have been collected and the fishery is being managed in a precautionary way. Because of its isolation and potentially dangerous ice conditions, it is thought that little or no IUU fishing has taken place in this region.

In recent years there has been concern over the effect of bycatch in longline and trawl fisheries on certain species groups, in pareticular macrourids (rat tails or grenadiers) and skates & rays. While reported annual catches to date are not high, skates and rays in particular tend to be slow growing and have relatively low reproductive potential.

Since 1998 there has been a small revival in the fishery for C. gunnari. Because the abundance of this species is naturally very variable, management has relied on the results of recent surveys to provide a short-term estimate of yield. Total annual catches of up to 4000 tonnes have been taken in the last decade, principally from South Georgia and Heard Island.

The fishery for Antarctic Krill, Euphausia superba started in the mid 1970s and quickly rose to a total of over 350,000 tonnes. Initially the about 60% of the catch was taken in the South Atlantic area, from South Georgia to the Antarctic Peninsula, with the balance coming from the Antarctic continental shelf region between the Weddell Sea and the Ross Sea. Since 1982 the proportion from the east Antarctic area has declined and has been zero since 1996. Unlike the finfish species, the catch of krill has been controlled more by market forces than regulations based on stock assessment. Currently, the long-term sustainable yield of krill in the South Atlantic area is assessed as 4.0 million tonnes, and that for East Antarctica between Prydz Bay and the Ross Sea as 450,000 tonnes. The peak in catches of about 500,000 tonnes in the early 1980s was mainly due to catches by the Soviet Union, where krill products were used in a wide variety of processed foods. The dip in catches in the mid-1980s is thought to be a result of concerns over high levels of fluoride in krill products. Once processing techniques were able to cope with this, catches reverted to nearly 500,000 tonnes until the early 1990s when the breakup of the Soviet Union resulted in a sharp decline in fishing effort. Since then, catches have been reasonably steady at about 100,000 tonnes per annum. Most of this catch is taken by Japan, which has had a steady annual catch of between 60,000 tonnes and 75,000 tonnes since 1986.