09 September 2013

Basking Shark Hotspot - Scotland

Basking Shark © Hebridean Whale and Dolphin Trust (HWDT).
Mark Hosford, volunteer for the Hebridean Whale and Dolphin Trust (HWDT), keeps us up to date with sightings from the west coast of Scotland.

"July was a poor month for basking shark sightings off the west coast of Scotland, with only 17 reports submitted to the HWDT by members of the public, most of these sightings contained only 1 or 2 individual sharks. When it came to spotting basking sharks, the HWDT research vessel Silurian fared a little better than the public. On the evening of the 26th July, while out on the teen team survey, the Silurian encountered a group of 30 or more basking sharks. The sharks were spotted as the boat approached a safe anchorage off the west coast of Coll and with the help of the teenage volunteers the crew conducted photo-ID on the sharks that were visible on the water’s surface.

August saw a massive increase in the number of basking shark sightings reported to HWDT. We received a staggering 66 reports of these ocean behemoths. To put this jaw dropping figure into some context, we received 47 sightings of basking shark last August and a total of only 45 sightings between January and July this year. While basking sharks sightings were reported from all around the Hebrides, three areas in particularly had very high numbers of sightings, these areas included the waters around the Isle of Arran in the Firth of Clyde, the mouth of the Sound of Mull and the waters around Coll and Tiree.  Not only has there been an increase in the number of sighting reports, there has also been an increase in the number of sharks seen in each sighting, with groups of 10 – 15 sharks commonly being seen. One group of approx. 40 sharks were spotted 6 miles west of Gunna Sound on the 6th August and another group of approx. 25 were seen off Canna on the 21st August.

HWDT were not the only organisation on the west coast interested in reports of basking sharks this summer. A team of scientists from Scottish Natural Heritage and the University of Exeter were in the Hebrides this July and August undertaking a basking shark tagging project. Despite the sparse sightings of basking sharks during July the team managed to tag a number of sharks with satellite tags, which will allow the team to follow the movements of the sharks and learn more their life history and habitat use in the areas around Coll and Tiree. To follow these tagged basking sharks, please click here.

Hebridean Whale and Dolphin Trust