The islands used to be home to 10% of the UK's Roseate Terns

Environmentalists are hoping to raise the numbers of Europe's rarest sea bird, the Roseate Tern.

Only 50 pairs are known to breed around Britain, and they have not bred on the islands since 1994.

In 2003, there was only one sighting on the islands. Ten years ago, they were home to 10% of the UK's population.

The scheme on the Isles of Scilly, which is being managed by the Isles of Scilly Wildlife Trust with the support of English Nature and the RSPB, is part of a national seabird recovery programme.

The islands' first tern warden, Ben Lascelles, has been monitoring nesting colonies of Common Terns and putting in protection measures to increase their breeding success rate.