Where do basking sharks live?

As our name suggests, basking sharks live here in Scotland – but this isn’t the only place they’re found, and we’re just one stop in their journey.

Basking Sharks can be found almost worldwide at different times of the year, with notable populations sighted between Scotland, Ireland, Norway, the eastern United States, Canada, Japan, New Zealand and the Mediterranean – some sharks have even turned up in Australia and a tagged shark ventured as far as the Amazon river basin! 

However, it’s not only distance they cover but also the depths! The name basking shark is a bit of a misnomer from medieval times as it was called a sunfish. This might suggest that they spend their time basking at the surface but in fact they only spend about 20% of their lives on the surface, whilst yo-yoing between depths of hundreds of meters as they follow their prey – copepods. A shark that was tagged at the surface in the Isle of Man in July 2007 disappeared, providing no tagged data until a few months later when it surfaced offshore from Newfoundland, Canada. Upon retrieval of the tag, it was found that it had travelled 10,000km and reached depths of 1600m following the contour of the seabed.

The basking sharks that we see in the Sea of the Hebrides MPA don’t usually arrive until mid-July, and only spend around 6-8 weeks here before moving on. Tagged data shows that most of these sharks will travel south, following the west Irish coastline, before crossing the Celtic Sea and making their way to the Bay of Biscay and even as far as the Canary Islands over Winter. This journey is then reversed with sharks arriving in Ireland in the Spring, and then leaving Ireland to travel to the Hebrides. There are also some separate populations that seem to reach us first by coming in from the Eastern Atlantic, some migrate back and forth between the East and West Atlantic, and some might not even leave at all.

It’s only really within the last two decades that these discoveries have come to light with advances in satellite tagging (and funding). It’s only really when you see their movements laid out like this that you realise that finding these migratory, deep-diving sharks can be be like searching for a needle in a haystack!