A stubborn pod of whales will be herded away from a NATO naval exercise again after they twice swam back to their original position.
Up to five bottlenoses returned to the Scottish loch and there are fears warships’ sonar systems could cause them distress.
Volunteers, Ministry of Defence personnel and the British Divers Marine Life Rescue service were today preparing a last-ditch bid to encourage them back out to sea.
A massive NATO naval exercise with aircraft carrier HMS Queen Elizabeth as the centrepiece is due to begin in Loch Long on Sunday.
The MoD wants to divert the pod out of the mouth of the River Clyde before then.
Julia Cable, of BDMLR, said: “We know there are five around but they split up so we cannot be sure how many are in the area.
“We will try and match up individuals and will look through images to try and piece together which have been where and when.
"They seem to be splitting into two groups.”
HMS Queen Elizabeth will be protected by seven Royal Navy Destroyers frigates and other ships, forming a Carrier Strike Group aimed at fighting on both the surface and the air.
Her deck is bristling with deadly F35-B fighter bombers from the RAF and US Marine Corps.
Military sources said the exercise, involving 14 nations, will go ahead on schedule.
An MoD spokesman said: “The Royal Navy takes its environmental responsibilities very seriously.
"It continues to work to reduce environmental risk.”
