Basking Shark

Latin name: Cetorhinus maximus
Global Distribution: Coastal/pelagic – found worldwide in boreal to warm-temperate waters around the continental shelves, and entering into brackish waters on occasions
UK Distribution: West coast (migration route)
Size: On average adult basking sharks grow to 6m-8m, but have been known to grow as big as 12m long
Diet: Zooplankton, krill, small fish.
Habitat: Found from the surface down to over 900m deep
Sources: SNH Commissioned Report 339 – Basking Shark Hotspots on the West Coast of Scotland: Key sites, threats and implications for conservation of the species
The Marine Conservation Society’s Basking Shark Watch – A Twenty Year Report
The Shark Trust’s Basking Shark Project Basking Shark Project
MarLIN’s Basking shark species review

The basking shark is the second biggest fish on the planet and the largest in UK waters. Its massive open jaw, spanning over 3ft wide, filters 2,000 litres of water per hour and sifts out zooplankton and small fish from coastal seas. The Basking Shark is what islanders might describe as a ferry-louper, a regular summertime visitor to the shores of Arran.

The numbers of basking sharks in Scottish waters are not known. By about the mid-18th century, Scottish fishermen had developed harpooning techniques capable of landing basking sharks and this continued on a relatively small-scale until the 1820s. Gavin Maxwell’s slightly ill-fated attempts to resurrect the fishery and set up a basking shark fishing station on Soay in the 1940s prompted a number of other fishermen to hunt basking shark commercially with variable success. The species has been fished as recently as 1994 by the Howard McCrindle. Now basking sharks are protected by law in the UK and any commercial value now flows more from their touristic interest than as a fishery stock.

Fun facts

  • They swim in schools that can range from 30 to 1,400 sharks.
  • The two halves of their genus name, Ceto and rhinus mean marine monster and nose respectively.
  • Their corpses are sometimes mistaken for the fossilised remains of sea serpents or plesiosaurs.