Basking Shark - Cetorhinus maximus
Status: Vulnerable … The basking shark is the second-largest fish in the world
Location: Visits UK waters between April and October, most commonly seen SW Cornwall, Isle of Man and west coast of Scotland.
Size: Can reach 11 metres long and weigh up to 7 tonnes
Habitat: Open ocean.
Main Threats: Basking sharks were once hunted for their liver oil, but, thanks to MCS lobbying, they’re now protected in UK waters. Basking sharks occasionally entangle and drown in fishing nets, but the MCS Basking Shark Watch data suggests their population in UK waters may be recovering.
Because of its size, their very large fins are the most valuable in international trade to Eastern Asia. Shark finning is the wasteful practice of cutting off a sharks fins and discarding its carcass at sea – due to there being no interest in its meat. Shark fins are of high value due to its traditional, luxurious status in Chinese cuisine. The strong demand for fins is contributing to the fishing pressure on shark populations around the world.
Basking sharks mate in the early summer months. One ovary contains a very large number of small eggs and the embryos hatch within the uterus. During the development of the embryos the mother produces infertile eggs for the embryos to feed off. The gestation period for a basking shark is around 12-36 months. It is believed that there is a 12 month resting period between each litter, which gives a 2-4 year interval between litters. This slow rate of reproduction makes basking shark populations highly vulnerable to over-exploitation. Very little is known about basking sharks and their whereabouts during the winter months.
Did you know?
- They feed on plankton, filtering 2,000 cubic metres of water per hour through their gills!
- Despite their size, basking sharks are harmless to humans.
- In summer months, when we are most likely to see them, basking sharks move slowly at the sea surface, feeding on plankton with their characteristic wide-gaped open mouths. This gives the impression they are basking in the sun, hence the name ‘basking shark’.
What MCS is doing:
- Finding out more about our enigmatic basking sharks through, Basking Shark Watch, the largest basking shark sightings database that we know of;
- Campaigning for better management of marine protected areas to protect basking sharks and their habitats from damaging activities;
- Campaigning for better water quality in UK seas, including at inshore basking shark habitats;
- Campaigning to reduce marine litter.