One of the last four female resident killer whales in the Hebrides has been found dead.
The body of the female orca -
The group -
The Hebridean Whale and Dolphin Trust fears their survival as a community is at grave risk.
The charity believes that the group is likely to become extinct in our lifetime, as no calves have been spotted with them since research began 20 years ago.
Biologist at the trust, Dr Conor Ryan, made the identification after matching Lulu's known eye patches, scars and unique marks from a photo of the dead whale taken by John Bowler, the RSPB officer on Tiree.
Her exact age is unknown but she was first seen off the Hebrides two decades ago. Female orcas can live to over 30 years.
Hebridean killer whale survival fears after female orca found dead
5 January 2016
The Hebridean Whale and Dolphin Trust said: "We have some sad news to report: one of the West Coast Community of killer whales known as 'Lulu' was found dead on Tiree.
"It is particularly sad to know that another one of these killer whales, unique to the British and Irish Isles has died.
"There may be as few as eight individuals remaining in this population, which has not produced calves since studies began."
Killer whale specialist, Dr Andy Foote, said: "It is very sad to lose this unique group.
"There are lots of potential contributing factors, many of them man-
"It may also be part of a very natural process, and when these killer whale populations colonise new areas, sometimes it works out and sometimes it doesn't."
A postmortem is to be held to try and determine the cause of death.