CCAMLR’s Ecosystem Approach in Practice

Impact of Fishing

CCAMLR has tackled a number of substantial problems relating to the direct effects of fishing on various components of the Antarctic marine ecosystem.

Incidental Seabird Mortality in Longline Fisheries (IMALF)

Longliners fishing for Patagonian toothfish set some 5 000 to 15 000 baited hooks during each set. These act as deadly lures for albatrosses and white-chinned petrels with thousands of birds being drowned when they are hooked and/or entangled trying to take the bait.

In 1989, CCAMLR took its first steps to minimise this ‘incidental mortality’. Vessels deploying longlines in the Convention Area now use various methods to reduce this catch. For example, longlines are set at night, offal is not thrown overboard during setting and streamer lines (or ‘scare’ devices) are deployed to minimise potentially damaging interactions between foraging seabirds and longlines. The opening of the toothfish season has also been moved to a time when fewer birds are likely to be in the Convention Area or proximal to fishing vessels. As one of their designated functions, scientific observers serving on board all Members’ longline vessels in the Convention Area monitor and record any deaths of seabirds during longlining. A notable success has been the observation that night-time setting alone has reduced albatross deaths by about 80% over the past three years. Despite these successes, CCAMLR estimates that in excess of 100 000 birds may have been caught by illegal and unregulated vessels fishing in the Convention Area between 1997 and 1999. In addition, many Antarctic seabirds are taken by longliners operating outside the Convention Area.

CCAMLR has publicised the IMALF tragedy widely. At its urging, other agencies (including the Food and Agricultural Organisation of the United Nations), fisheries commissions and organisations have taken similar steps to protect Antarctic seabirds feeding and/or wintering in areas outside the Convention Area. The problem of IUU fishing impacts on seabird populations of interest to CCAMLR has yet to be resolved despite positive efforts to bring such fishing under control.

Effects of Trawling      [Return to table of contents]

Up to the end of the 1980s, most vessels fishing for finfish in the Convention Area were trawlers. Heavy trawling gear is known to scrape and plough up the seabed which not only stirs up the sediments but also destroys animals living on the sea floor. Although such impacts on the fragile and slow growing communities of the Southern Ocean have not been assessed, they are likely to be significant locally and long lasting.

Coupled with these concerns, and in order to protect key portions of the stocks concerned, CCAMLR has banned bottom trawling for mackerel icefish (Champsocephalus gunnari) around South Georgia as well as for a number of demersal fish that are taken only by bottom trawling.

Entanglement in Marine Debris      [Return to table of contents]

In 1990, CCAMLR’s Scientific Committee reported that fishing net fragments and plastic packaging bands were impacting on Antarctic fur seal populations at South Georgia. CCAMLR promptly intensified its campaign to promote compliance with the International Convention for the Prevention of Pollution from Ships (MARPOL) and disseminated substantial information on the potential ecological damage likely to be associated with marine debris in the Convention Area (http://www.imo.org/imo/convent/pollute.htm#MARPOL). A key facet of this initiative was to improve awareness of the issue amongst vessel operators. It was also recommended that if fishers had to jettison debris, care should be taken to eliminate plastic waste and to ensure that the potential for any impact by the debris associated with fishing is minimised (e.g. by ensuring that any plastic packaging material capable of forming loops is cut). Although CCAMLR continues to monitor the overall levels of marine debris in the Southern Ocean, these are still too high. It is also doubtful whether vessels engaged in IUU fishing comply fully with either MARPOL or CCAMLR requirements. CCAMLR Members report annually on both the incidence of marine debris encountered in the Convention Area and their impact, including entanglements, on marine mammals and seabirds.

Impact of Fishing on Non-target Species      [Return to table of contents]

Bottom Trawling         [Return to table of contents]

Bottom trawls do not discriminate between target and non-target species, catching whatever the trawl encounters. Therefore, the abundances of species NOT targeted by a fishery (i.e. the ‘by-catch’) are likely to be affected. In the mid-1980s, for example, several by-catch fish species in the trawl fisheries around South Georgia and the South Orkney Islands were unintentionally overfished.

CCAMLR’s management approach requires it to take account of the effects of fishing on non-target species. In many cases, this has meant that total allowable catches (TAC) for target species are linked to allowable by-catch. A fishery may thus be closed when it reaches the TAC level for the by-catch of a particular species, even if the TAC for the target species has not been reached.

CCAMLR has directly prohibited fishing when the risk to by-catch species is thought to be too great, as was the case with the mackerel icefish fishery around the South Orkney Islands. Fishing for this particular species has been confined to the use of midwater trawls only, as the potential for by-catch is lower.

Midwater Trawling for Krill        [Return to table of contents]

Midwater trawling for krill does not distinguish between species and in addition to krill, the fine-mesh nets being used catch fish larvae and juveniles. To ascertain whether such catches exhibit any potential to affect the fish stocks concerned, scientific observers on board krill trawlers now collect data on by-catch. Initial results suggest that there are large spatial and seasonal differences in the occurrence of juvenile fish in the krill catch which make it difficult to objectively assess the extent of the problem. CCAMLR Members are now intensifying their collection of information so that CCAMLR can be in a better position to assess more precisely where/when fish are most vulnerable to by-catch by the krill fishery and to identify an appropriate course of action.

Impact of Fisheries on Target Species       [Return to table of contents]

New and Exploratory Fisheries       [Return to table of contents]

In an ideal world, fisheries managers should collect all the information required to develop the sustainable and scientifically defensible management of a new stock before commercial fishing is allowed. Comparisons can then be made of the status of the stock before and after fishing begins, with management action being adjusted accordingly on the basis of some desired status for the exploited stock. In the real world, new fisheries are often exploited – even overexploited – well before the necessary information is available or even collected. CCAMLR’s precautionary approach attempts to balance these two realities in a way which strives to minimise the risks of irreversible changes in the status of targeted stock.

CCAMLR recognises that fisheries need to be managed from the time they start and has thereby developed conservation measures to be followed before any new fishery commences. In CCAMLR terms, a ‘new’ fishery is one for a species and/or on a ground that has not previously been fished. It is also an established fishery where there is an intention to use a new fishing technique. There is a requirement at the ‘new’ fishery stage to collect information on the target as well as dependent species, and the catch or effort (or both) may be limited. In CCAMLR parlance, a new fishery lasts for one year unless no catch is taken at which time it retains its classification.

In the second year, the fishery becomes an ‘exploratory’ fishery. Both CCAMLR’s conservative approach and data collection requirements continue to allow for a full assessment of the fishery and stock(s) to be developed. A data collection plan must be followed and a research and fishery operation plan produced. All such plans are reviewed each year by the Scientific Committee. The crab and squid fisheries around South Georgia are being managed in this way.

Most recently, CCAMLR has instituted a requirement that exploratory toothfish fisheries follow clearly defined experimental fishing plans. This approach strives to maximise the data collection potential of fishing vessels while ensuring that unacceptable damage is not inflicted on stocks for which key management data are missing. Therefore fishing vessels are required to undertake some research on stock distribution and abundance as part of their development of either new or exploratory fisheries. This requirement applies to both toothfish and crabs.

Similar regulatory criteria are being developed for reopening fisheries that have lapsed or been closed.

Illegal, Unregulated and Unreported Fishing      [Return to table of contents]

As already indicated, the problem of IUU fishing on toothfish is continuing to vex CCAMLR’s application of the ‘precautionary approach’. The reason for this is that IUU fishing has resulted in substantial toothfish catches and these are well above the best scientific estimates of the aggregate global limit for the species in the Convention Area, particularly in the Indian Ocean. Furthermore, the continued lack of information from IUU fisheries severely complicates CCAMLR’s efforts to determine future toothfish stock trends in certain areas. Together, these factors contribute to uncertainty surrounding the status of such stocks and also indicate that their future sustainability is likely to be compromised.

CCAMLR has responded to the management challenge posed by IUU fishing by developing an integrated policy of conservation measures. This serves to increase the gathering of essential data and improve compliance with catch limits. Relevant measures include improved data-recording procedures, the promotion of closer cooperation between CCAMLR Parties and non-Parties, the need for Flag States to authorise their vessels to fish in the Convention Area and a process to monitor the international toothfish trade (see below).