Huge whale strands on north coast

22 February 2010

The body of a huge whale has been found on the north coast of Cornwall. The Cornwall Wildlife Trust Marine Strandings Network believes it to be a fin whale, which had first been reported floating close to the shore off Pendeen.

The whale was originally spotted by Jean Lawman, a keen naturalist who regularly watches out for marine wildlife. Jean saw it about three kilometres offshore through her telescope and realised that it was too big to be any other species. Fin whales are often seen at this time of year, but sadly this one appeared to be dead, so it was reported to the Marine Strandings Network Hotline. Unfortunately, the whale did not beach and continued to float on the tides.

Five days after the first sighting, the Marine Strandings Network's Hotline was alerted again to the whale after it had been seen near Porthtowan. Remarkably, it had floated 37 kilometres ENE along the coast from its first position. On this occasion, as the tide receded, the animal came to rest in a small cove where it was examined and recorded by Gary Hawkins, one of the Network's team members.

Gary explains "It's hard to describe just how massive this whale was. Even looking down on it from the cliff top above it looked huge, it was the length of an HGV lorry! I measured it at nearly 17 metres and the length of one of its flippers alone was 2.5 metres. But then, it is the second largest animal on earth!"

Although the whale was breaking up, Gary was able to take samples from it for the Institute of Zoology in London, which authorises the Strandings Network to collect samples on their behalf so that more can be learnt about these amazing animals. As Gary observed, "It was amazing to attend this animal in death, but can you imagine a mammal this size swimming in our waters? It's very humbling."

The cause of the whale's death was not obvious from examining her, but fin whales are known to be the species most affected by ship strike. Although the fin whale is one of the fastest whales in the sea, and can travel at speeds of up to 40 km an hour, it can still be caught unawares when sleeping or resting on the surface and few whales survive a collision with a ship.

Fin whales can grow up to around 25 metres long, with the average at around 20 metres, and a female whale can weigh up to 120 tonnes. Remarkably, they can live for up to 90 years. Although they are inaudible to the human ear, the whales' low frequency calls can be heard by other whales some 850 kilometres away.

Since the 1990s they have been seen during most winters off the coast of Cornwall. Their vertical blows are easily visible from some two miles away without binoculars, and they may stay close to the surface for about a minute and a half minutes each time they surface. They then dive to depths of up to 250 meters, although they are also known to enter shallow water, and each dive can last between 10 and 15 minutes. They have a varied diet of fish and squid, but may also eat krill and copepods. With their huge mouths, which make up about 25% of their body length, they can take in up to 70 cubic meters of water in one gulp.

Fin whales numbers are probably rising steadily since the cessation of commercial whaling, which vastly reduced their numbers. However, Japan and Iceland have now resumed hunting these whales and their intention is to increase takes in the near future, despite the fin whale being considered an endangered species. In the summer of 2009 for example, 125 fin whales were caught by Icelandic fishermen.

The public are urged to report any dead marine creatures to the Cornwall Wildlife Trust Marine Strandings Network on 0845 201 2626. However, the Network strongly advises not touch any stranded animals as they may pose a health risk.