Tomorrow marine biologists start tracking sharks basking around Tiree, Coll and Hyskeir 

An exciting project which scientists hope will reveal the secret life of large sharks visiting Scottish waters will begin in Hebridean seas tomorrow – Friday 13th July.

Marine biologists from Scottish Natural Heritage (SNH) and the University of Exeter will attach satellite tracking tags to 20 basking sharks in the seas around the Inner Hebrides, off the west coast of Scotland. Once fitted, the tags will allow people to track the movements of the sharks on the SNH website in close-to-real time. (We give the link to this facility below.)

The tags will provide information on the location and behaviour of the sharks during the summer when they can be seen feeding in large numbers at the surface. They will also track the sharks for several months afterwards, helping scientists understand if the sharks travel to deeper water around Scotland and further afield over the winter.

The tagging work will take place in the waters around Coll and Tiree and the small island of Hyskeir (with its landmark lighthouse) near Canna.

Research has shown these areas are hotspots for basking sharks, with consistently large numbers sighted there during the summer months.

Even though basking sharks are seen in many places round Scotland, displays of social and courtship behaviour, such as breaching and following each other nose-to-tail, have only been observed in these areas, suggesting they are important for key stages in the life cycle of the sharks.

Dr Suz Henderson from SNH, who is managing the basking shark tagging project says: ‘We’re really lucky to have the world’s second largest fish visit our waters every summer but we know very little about their movements throughout the rest of the year.

‘We want to know how the sharks use the waters between Skye and Mull and how long they remain in the area.

‘We’d also like to find out how important this area is in the life cycle of the sharks, and if some areas are used more than others. The results from this project will help to answer these questions.

‘In addition, an area between Skye and Mull (Ed: which would include the waters around Tiree and Coll) has recently been identified as a place where it might be appropriate to develop a marine protected area (MPA) to protect basking sharks. The tagging work will help determine if an MPA is an appropriate way to safeguard these magnificent animals.’

The tags – attached to the sharks using titanium darts and darting poles – will record information on the movement of the sharks, including depth and water temperature. The tags will be shed by the sharks after several months.

Dr Henderson says: ‘The tags might be washed up on beaches after being released from the sharks and if we are able to retrieve them they will provide us with additional information. We’ll be asking the public to keep an eye open for them and help us recover as many as we can.’

Dr Matthew Witt of the University of Exeter says: ‘Although they have captured the public imagination, we actually know relatively little about how basking sharks live. This is a fantastic opportunity for us to find out more about the movements and lifestyles of these fascinating creatures.

‘This project will use some of newest animal tracking technology available for marine species that allows us to know where the sharks are with near GPS accuracy. This is a hugely challenging project – not least because we are at the mercy of the weather and sea conditions – but the results will provide invaluable in our quest to uncover the secrets of these giants of the sea and help to protect them.’

The area where the study is being undertaken overlaps with an offshore wind farm proposal west of Tiree, known as the Argyll Array – and, perhaps more widely if less formally, as the Tiree Array.

The tagging project will provide information about the use of this area by the sharks, giving additional confidence to the advice which SNH provides to Marine Scotland as the development goes through the licensing process.

Tracking the basking sharks online after they are tagged – starting tomorrow – go to the SNH website here.

It would be naive to see environmental issues in the driving seat of this welcome exercise. SNH has recently come under fire in its omission from a report of data on marine and airborne wildlife species that would be affected by offshore wind and marine energy installations.

Thanks to the vigorous and highly informed No Tiree Array campaign, there is widespread awareness of the massively out of scale proposals of Scottish Power Renewables for this array. The Scottish Government, which has taken to itself the decision taking power on this plan has delayed a decision until 2016.

SNH can be reasonably hammered for their deficiencies, compromises and the erratic or, on occasion, non-existent research base used to support their opinions, but this research initiative and its transparency in making the tracking website openly available, is to be commended.

This is the start of the objective science we need to underpin our thinking and decision taking in on and offshore renewables.

The documented behaviour of the basking sharks will supply evidence of genuine and objective use in our collective coming to understand the impacts of proposals on offshore renewables.

This is only the beginning, There is a serious volume of research to be done before secure decisions on renewables development can be taken, one way or the other.