Basking Sharks are common in the traditional knowledge of indigenous peoples of Vancouver Island, Canadian Pacific. Salmon net fishermen in Barkley Sound, Vancouver Island, complained of damage through accidental basking shark catches in the 1940s. The Department of Fisheries and Oceans instigated a shark eradication programme in the 1950s. Clemens and Wilby (1961) state that Fisheries vessels killed ?several hundred? in Barkley Sound up to 1959, to reduce salmon net bycatch. Darling and Keogh (1994) state ?Basking sharks are rarely sighted in Barkley Sound today, suggesting that the majority of the population in that area were killed.? It seems that this stock of Basking Sharks was significantly depleted over a period of just a few years and has not yet recovered. A summer Basking Shark fishery started at Achill Island, western Ireland in 1947, using set nets to entangle sharks. It peaked in the early 1950s, when 1,000?1,808 sharks were taken each year. In the early 1970s only 29?85 sharks were taken annually, a decline of over 90% in 20? 25 years. Re-capitalisation of the fishery in 1973 failed to increase yields locally and it closed in 1975, despite high oil prices. Parker and Stott (1965) and Horsman (1987) attributed the decline and collapse of this fishery to the overfishing of a local stock. Berrow and Heardman (1994) noted that there were still very few observations of basking sharks along the whole west and north-west coast of Ireland in 1993, and Achill Island fishermen reported fewer than 10 sharks sighted annually (Earll pers. comm.). This fishery appears to have depleted the population to such an extent that it has still not recovered some 40 years later. A wide-ranging Norwegian fleet has undertaken the major basking shark fishery in the northeast Atlantic from April to September in most years. Catches were high (>1,000 and up to >4,000) from 1959?1980 (Kunzlik 1988, ICES data, in Anon. 2002c). The Norwegian quota in European Community waters was 800 t (liver weight) in 1982, 400 t (approximately 800?1,000 sharks) in 1985, subsequently reduced to 200 t, 100 t, and to zero in 2001. Because basking sharks are taken by fishing vessels targeting small whales, increased restrictions on whaling activities and ageing vessels have reduced fleet size. The decline in this fishery has also been attributed to the falling value of Basking Shark liver oil, as a result of the competition from deepwater shark fisheries. Landings rose slightly in the early 1990s, when the fishery was being sustained by high fin prices (ICES 1995), but have since declined to very low levels, despite steeply increasing fin values. The majority of fins landed by Norway have been exported to Japan (Anon. 2002c). Since the precise location from which the basking sharks were taken is only identified by ICES sea area, it is difficult to detect and evaluate trends in catches, effort, and hence population, but the declines appear to be related to population trends and driven by fisheries and trade demand (Anon. 2002c). An intensive targeted Japanese Basking Shark fishery, utilising liver oil, shark fin and meat, took place in spring off Nakiri, Shima Peninsula, in the 1960s and 1970s. An estimated 1,200 sharks were harpooned from 1967?1978, peaking in 1972 when more than 60 sharks were sold at market in one day. Catches declined from about 150 sharks in 1975, to 20 in 1976, nine in 1977 and six in 1978. The fishery closed a few years later. In the 1990s, only 0? 2 Basking Sharks were being sighted each year off Nakiri during migration (Yano 1976, 1979, Uchida 1995). Basking sharks are sometimes landed and sold after becoming entangled in set nets or pot lines, or caught in trawls, but bycatch (whether landed or discarded) is rarely reported. Exceptions are reports by Lien and Fawcett (1986) on an incidental fishery for basking sharks by salmon and cod set nets and deepwater trawls in Newfoundland, and Francis and Duffy (2002) on incidental capture in deepwater fisheries off New Zealand. Incidental shark catches in Newfoundland increased in 1981 when a market developed for the fins and liver. When there is no market for the sharks? fins and livers, salmon fishermen generally remove their gear from the water to prevent damage when basking sharks are known to be in the area. If there is a market, any sharks caught are killed and landed.
Berrow (1994) estimated that 77?120 sharks are taken annually in the bottom set gillnet fishery in the Celtic Sea. Fairfax (1998) reports that basking sharks are sometimes brought up from deepwater trawls near the Scottish west coast during winter. Bycatch in Isle of Man herring fishery is about 10?15 fish annually and a further 4?5 entangled in pot lines, (K. Watterson in litt.). Local fishermen estimate an unreported bycatch of up to 40 Basking Sharks per year in one large bay in south-west England (C. Speedie pers. comm.). In contrast to these relatively large coastal bycatches, observer data from oceanic gillnet fleets suggest that only about 50 Basking Sharks were among the several million sharks taken annually offshore in the Pacific Ocean (Bonfil 1994). Habitat loss or degradation is not considered to be a serious problem for this species.
Following notes added by Lucy Harrison (firstname.lastname@example.org) via Sarah Fowler May 17th 2010
Later in 2005, the species was listed in Appendix I and II of CMS. Appendix I means that Parties are required to provide strict protection.
In 2006 ICES issued this advice, which is still current:“No targeted fishing for basking shark should be permitted and additional measures should be taken to prevent bycatch of basking shark in fisheries targeting other species. A TAC should cover all areas where basking sharks are caught in the northeast Atlantic. This TAC should be set at zero.”
This advice was adopted in 2007 and the zero TAC covers all areas of the NE Atlantic where basking sharks may be caught.
Norway ALWAYS implements ICES advice (and indeed, unless they take out a reservation, also other MEA measures – unlike many other States). Their basking shark fishery was therefore closed in either 2006 or 2007, I forget which but probably the latter. They are presumably still landing bycatch, because Norway prohibits discards, but fishermen are not paid full market value for catches for which they do not have a license – only enough to cover the cost of bringing home the catch. This means that they will be avoiding basking sharks wherever possible.
Because of the CMS Appendix I listing, basking shark is also an EU prohibited species: “It shall be prohibited for Community vessels to fish for, to retain on board, to tranship and to land the following species in all Community and non-Community waters” Every year, however, we get reports of basking sharks being caught, landed and put on sale illegally in the EU. So, small scale bycatch and utilisation is definitely ongoing even in areas where the species is strictly protected.
Elsewhere: NZ is the only place where there is still a fairly large utilised basking shark bycatch (in trawls over hoki spawning grounds). The fins are exported under CITES license to East Asia. NZ allows finning.