Whale deaths linked to military sonar use

Military sonar, used in a Nato exercise that involved the Royal Navy, was responsible for killing four Cuvier's beaked whales on 26th of January 2006, off Spain's Almeira coast. It is the first time that the Royal Navy has been implicated in whale deaths.

The two males and two females that stranded were in good body condition, three of the carcasses were in fresh condition and the fourth was moderately decomposed when necropsied. Two animals were found alive and two were found dead. The two live animals appeared to show clear signs of “sickness” and died soon after being found.

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."

All the four animals showed a "Gas and Fat Embolic Syndrome". The pathological findings in the Almeria mass stranding is very similar to previous referenced in several other beaked whale mass strandings associated with military naval exercises -Bahamas,2000; Canary Islands,2002, 2004). In all of these cases mid-frequency active sonar was used before or during the time of strandings. The whales involved were mainly of the beaked whale family also.

The full report of the Almeria strandings will be ready by late summer.

photo images (c) G Cresswell/Francisco Bonill