Pearl mussels are in danger of becoming extinct across Scotland

About 200 rare pearl freshwater mussels in the Outer Herbrides have been moved because they were running out of water.

Scotland is home to half the world's population of freshwater pearl mussels and there are thought to be just 61 breeding sites left in the country.

The unnamed location in Harris is one of the most important sites for the species in the country.

Staff from Scottish Natural Heritage moved in when the rare molluscs got clogged up with gravel and peat.

Clean water

The mussels, which are protected by law, have been moved to another location on the same waterway and SNH said early indications were that the operation looked like being a success.

Roddy MacMinn, the SNH area officer who was involved in the operation, said the mussels had settled in to their new surroundings.

"The project should have a high chance of success - a check a few days later found that the moved mussels had opened up (started to filter feed), a sign that they were happy in their new locations," he said.

The conservation body said the precise location of the mussels was not being released in a bid to protect them from poachers.

It is against the law to intentionally or recklessly kill, injure, take or disturb the mussels, or their habitat.

It is also illegal to sell or advertise pearl mussels for sale without a licence from the Scottish Executive.