Whale survey boat shadows Nato exercise Joint Warrior

The survey work will be done from the Hebridean Whale and Dolphin Trust's yacht Silurian

A marine conservation charity's yacht is shadowing one of Nato's biggest military exercises off the west coast of Scotland.

The Hebridean Whale and Dolphin Trust (HWDT) boat Silurian is normally used for surveys of whales, dolphins and basking sharks.

It has been equipped with new equipment to help monitor changes in marine life behaviour during Joint Warrior.

The 13-day exercise involves 30 warships and submarines.

HWDT has shadowed the exercise before, but this year has added video range tracking kit to the Silurian's monitoring equipment.

The equipment allows volunteers on board to calculate changes in the speed of whales and dolphins, and assess whether they are fleeing from military activity.

The trust said it discusses with the Ministry of Defence about ways of reducing interference to marine life.

Joint Warrior involves more than 6,000 personnel from 12 nations

Joint Warrior is held twice a year - in April and October - and involves North American and European members of Nato.

This April's exercise was the largest in the event's history.

The latest exercise also involves 60 aircraft and about 6,300 personnel from 12 nations.

In April 2013, The Royal Navy took steps to avoid two areas off Scotland where whales were spotted.

Some training as part of Exercise Joint Warrior were altered to avoid Portmahomack, in Easter Ross, where three long-finned pilot whales were stranded.

The navy also noted, and avoided, the location of a sperm whale off Mull.