Royal Navy sonar blamed for deaths of four whales

Secret sonar, used by the Royal Navy in a Nato exercise, has killed four whales, The Independent on Sunday can reveal.

A post-mortem on four Cuvier's beaked whales, stranded on Spain's Almeira coast at the end of January, points to the sonar, which was being used by a British warship in the area at the time. It is the first time that the Royal Navy has been implicated in whale deaths.

The Ministry of Defence yesterday admitted that the sonar "has the potential to cause problems for the marine environment".

An investigation by The Independent on Sunday has revealed that military sonar is killing thousands of whales. Some experts suspect that it disorientated the northern bottlenose whale which got lost in the Thames in January.

The post-mortem on the Cuvier's beaked whales by the University of Las Palmas de Gran Canaria concludes: "Based on current scientific knowledge, and the pathological findings in this study, the most likely cause is anti-submarine active mid-frequency sonar used during the military naval exercises."

Tests have revealed that the Sonar 2087 system used by the Royal Navy can cause sea mammals to become disorientated. HMS Kent, one of the ships in the Nato exercise, is equipped with it.

The Ministry of Defence said yesterday: "We use sonar in an environmentally responsible way, working closely with scientific organisations to carry out environmental impact assessments that aim to provide a sustainable balance between the requirement for essential training and the need to avoid causing significant adverse impact on the marine environment."