Basking Shark Project

About basking sharks

The basking shark (Cetorhinus maximus) is the UK’s largest fish and one of the biggest animals we find in the sea, it can grow up to 12m in length and weigh about 7 tonnes. Worldwide is beaten in size only by the aptly named whale shark. It can often be seen, at the surface, with its mouth wide open trawling for its prey - plankton.

In the summer months we most often see them in coastal waters off the Cornish coast, the Hebrides, English Channel and Irish sea, where the waters are most productive. In the winter they tend to stay deeper to continue feeding. From satellite tracking studies of individual animals we know that they can be very wide ranging. One animal was tracked from the English Channel up to the Hebrides, 1878 km in 77 days. They have also been tracked out to the continental shelf edge in search of plankton. For more information on the tagging project go to www.cefas.co.uk

History of the basking shark

Historically, from 1700’s, the basking shark was the target of a healthy shark fishery, which caught the animals for their liver oil. This fishery declined as the oil subsidy was withdrawn. However smaller fisheries have existed for basking shark since 1945. It is estimated 105,000 animals have been taken from the north east Atlantic since 1945. The last remaining fishery (based in the Firth of Clyde) closed in 1995.

The basking shark is now protected by law and all hunting is illegal within 12 nautical miles of the UK shore. However hunting is still permitted out side this zone and Norway still holds a permit to take basking sharks from EU waters. The basking shark was finally listed on Appendix II of CITES in 2002 (an international agreement designed to control trade in fauna and flora) and joined a very small number of fish species to enjoy CITES protection. This listing doesn’t stop the shark being fished but it does require those who trade in its parts to obtain export/import permits. But for the basking shark, whilst protection on paper is a major step, unless the CITES listing is enforced and management action based in solid research, the species may continue to decline.

One of the problems is that we do not know enough to make well informed management decisions. We need to find out more about the basking shark lifecycle in order to protect key areas, especially those outside the 12 mile protection zone. To address these shortfalls in information HWDT is involved in a major new nationwide basking shark project headed by the Marine Biological Association has been initiated. HWDT is a partner in this project. Other members include the Shark Trust, Marine Conservation Society, the Wildlife Trusts and IFAW.

HWDT is involved in the following ways