The basking shark (Cetorhinus maximus) is the largest wild animal resident in the UK, and the second-largest fish in the world (after the whaleshark, Rhincodon typus, which only occurs in warmer waters).  They can reach 11m (36 ft) in length and weigh up to 7 tonnes - that's approximately the size and weight of a double-decker bus! Watch great footage shot by Dan Burton

Basking sharks are seen all around the UK and Irish coast, but are most often sighted along the West coast of the UK, and both the East and West coasts of Ireland.

Little is understood about the distribution, population size, and biology of this gentle giant.  What we do know (see fact file and threats pages) raises concerns, and the species is listed as 'vulnerable' worldwide, and 'endangered' in the NE Atlantic, on the IUCN Red List of Endangered Species.

MCS promotes and collects public sightings, through the Basking Shark Watch (BSW) project.  This has developed into the UK's largest and most comprehensive database on basking shark distribution and behaviour.  The data is regularly analysed, and the results published - and used to promote species conservation measures.

TO REPORT A SIGHTING, CLICK HERE