The high number of whales dying in the seas off the Western Isles has caused alarm.
Some 58 bodies washed ashore over the last month in west Scotland and Ireland are all thought to be linked to an unknown event west of the Hebrides.
Most are Cuvier’s beaked whales while some are True's which live in deep water near the continental shelf.
The UK and Irish governments are carrying out a joint investigation.
One was found dead on the shore at Baleshare, North Uist, last week.
Six whales in total were discovered in Uist and Islay -
Others have stranded along the west coast bringing the Scottish total to 38.
At least 19 have washed onto beaches in Ireland and another in Northern Ireland.
Experts fear the numbers are much higher as bodies may be drifting on the ocean.
Cuvier’s beaked whales are susceptible to certain types of naval sonar and acoustic survey methods.
A Royal Navy spokesman said: “There is no evidence that the deaths of these marine mammals have been attributed to any Royal Navy sonar operations, trials or exercises.
“We take our environmental responsibilities very seriously and continue to work with the relevant UK authorities to reduce any environmental risk.”
Mystery of whale deaths in Western Isles
10 September 2018