Second year of basking shark tagging gets underway

The tags, which let the public follow the movements of a number of the sharks online, will collect data that will give the team an insight into their behaviour during the summer months.

The work is part of a wider programme of marine research led by SNH and Marine Scotland, to help Government and others plan for the sustainable management of the sea. Results from the tagging project will help the Scottish Government decide whether a Marine Protected Area should be put in place to safeguard the sharks and help balance environmental interests with industry and recreation.

The tagging project, which began last July, was set up to find out more about the life cycle of the large numbers of sharks that gather around the islands of Coll, Tiree and Canna every summer. Some of the 20 sharks tagged last year stayed in the area between 5 and 57 days before the tags detached, the sharks moved deeper or they swam south. Depth data collected so far has shown that sharks mainly occupy the top 250m of the water column, although two sharks were recorded down at 1000m, off the edge of the continental shelf.

Dr Matthew Witt from the University of Exeter’s Environment and Sustainability Institute at the Cornwall Campus said: “Working with SNH is an exciting opportunity - it allows us to unite our unique capabilities to help improve knowledge on the life history of basking sharks, with the long term aim of delivering a sustainable future in our increasingly busy coastal seas.”

Dr Suzanne Henderson from SNH, who is managing the project, said: “It’s great to be working with Matthew Witt and his team from the University of Exeter again on this fascinating project. The second year of tagging will build on last year’s work, helping provide insights into shark behaviour year on year and identify any trends in the behaviour of sharks in this area. We’re tagging more sharks this year to increase the confidence we have in the results and so we can look more closely at how behaviour differs among individuals.

“We hope the public will enjoy taking part again by following the progress of 15 of the sharks online. Last year half of the tags stayed on the sharks for over 90 days, with one detaching from its shark (Elgol) after 326 days to the south west of Portugal! We hope this year is just as successful.”

SNH and UoE are asking anyone who finds a tag around the shores of the UK to get in touch. The tags are silver/grey, torpedo or oval shaped, 15 to 18 cm in length with a small antenna and may still have a plastic tether attached. If found please pick up and contact the SNH office in Oban on 0300 244 9360, or email baskingsharks@snh.gov.uk. There is a reward available for each tag returned.

To track the basking sharks online after they are tagged, go to: http://www.snh.gov.uk/about-scotlands-nature/species/fish/sea-fish/shark-tagging-project/