SCIENTISTS hope to uncover the secrets of basking sharks by tracking their movement in waters around the UK.

A total of 27 sharks have been tagged in a project to find out more about their seasonal behaviour.

A team from Scottish Natural Heritage (SNH) and Exeter University attached small tags to the fins of sharks around the islands of Tiree and Coll in the Inner Hebrides this summer.

Tags were attached to the dorsal fin of the sharks with a titanium dart using an extendable dart pipe.

Members of the public can now watch the progress online of 15 sharks whose tags provide information on their position each time they surface.

The others tags will collect data on depth, temperature and light levels over several months and then detach from the shark, floating to the surface to transmit data to satellites.

Much more data can be collected if the tags are retrieved and the team is appealing to anyone who finds a silver-grey, torpedo-shaped tag around the shores of the UK to get in touch.

Dr Suzanne Henderson, from SNH, is managing the project which is now in its second year.

She said: "Although we know a lot about basking shark biology and worldwide distribution, surprisingly little is known about their seasonal movements.

"The information we get from these tags will add to the results from the work we did in 2012, helping us build up a picture of the sharks' behaviour throughout the year."

Basking sharks can grow up to 36ft long and weigh up to seven tons, but feed entirely on plankton. They can live for up to 50 years.

For generations they were hunted for the high oil content of their large livers and more recently for their big fins.

The migrating species is most often seen in coastal areas in the summer and autumn when plankton are abundant at the surface of the water.

Basking sharks in the North East Atlantic are recognised as endangered and trade in their body parts is restricted by the Convention on the International Trade for Endangered Species.