Marine experts are looking for a valuable shark-tracking device which is expected to be washed up on a beach.

Seasonal strollers have been asked to help in the hunt for the tag as they walk along Essex beaches, and shark trackers have offered £50 to anyone who finds it.

The device, which is safe to handle, holds valuable data about the lifestyle and habits of the mysterious basking shark, which disappear from view for up to six months a year.

Data from the tags will help the Government in the fight to make the creatures an internationally protected species.

Scientists have been tracking the basking shark, which is the world's second largest marine fish, since May.

And it is thought a tag, which would have popped off the shark as it is programmed to do, is floating in the direction of East Anglia and is likely to be brought up on the tide soon.

Anyone finding a shark tag should send it to Dr David Sims, Marine Biological Association, Citadel Hill, Plymouth, PL1 2PB.

Published Friday December 28, 2001