On August 31, two Northern bottlenose whales (the same species as the whales which came into the Thames in January this year), stranded at Skegness on the east coast of the UK. British Divers Marine Life Rescue, the UK's foremost team experienced in marine mammal rescue, were immediately underway in an attempt to assist the animals.

The female whale died shortly after stranding, and after initial examination it was decided that as the male was still alive and appeared to be healthy, the plan was to refloat the animal just before midnight at high tide. Once the boat and pontoons were put into place the animal was aided into position ready for refloat.

The whale was eventually released back into deeper water but sadly at first light this morning, the animal was found dead. There are many reasons why strandings of this type occur, however even if a post mortem is carried out, this can still prove difficult unless a definite indication of death is found.

Northern bottlenose whales are perhaps the best-known members of the beaked whale (Ziphiidae) family, yet there is still a lot to learn about this remarkable species. So what do we know already? We know that this species belongs in the deep ocean, not shallow estuaries or even shallow seas like the North Sea. Studies have shown that its principal habitat is continental shelf edge waters and underwater canyons over 700 metres deep and that they feed primarily on deep-sea squid of the genus Gonatus. Greenland halibut and herring are also important prey. They grow to some 10 metres and are toothless except for two small teeth in the lower jaw of males. They are among the deepest divers, regularly diving to depths of over 1000 metres in search of prey.

They were previously widely found in the North Atlantic, but were heavily whaled by Canadian, British and Norwegian whalers during the 19th and 20th centuries, until the International Whaling Commission designated them as a‘protected stock’ in 1977. Close to 66,000 whales were caught between 1882 and 1972. Unlike other beaked whales, Northern bottlenose whales are inquisitive of vessels, which, combined with their innate care-giving behaviour, led to the capture of entire pods. Northern bottlenose whales are now restricted to a few mostly arctic and sub-arctic regions including the coast of Labrador, Davis Strait and the waters of Iceland and Norway. The status in these regions is unknown. This species is also sighted in the Bay of Biscay and around the Azores. The best-known population is approximately 130 individuals that are resident year-round in a deep-sea canyon off the coast of Nova Scotia, Canada, called the Gully.

Their presence and apparent isolation was a major factor in establishing the Gully as a Marine Protected Area, which protects this and other marine life from potential threats such as trawl fishing and oil and gas exploration. The challenge now is to understand the wider status of this charismatic and elusive species.

source: Marine Connection/Ross Compton
images copyright: Jason Carter/BDMLR