GRAY WHALE IN MEDITERRANEAN (Via Lindsay Selby and Dr Darren Naish)

A gray whale has appeared off the coast of Israel, shocking conservationists. Gray whales are thought to be extinct across the Atlantic Ocean, so the appearance of an individual within the Mediterranean Sea is a major surprise. The whale may have inadvertently travelled a huge distance from its natural habitat thousands of kilometres away in the Pacific Ocean.

However, it raises the possibility that gray whales have returned to former haunts in the western hemisphere.

Photographic ID

Once, three major populations of gray (also spelt grey) whale existed: in the western and eastern North Pacific Ocean, and in the North Atlantic. However, the North Atlantic population of gray whale became extinct sometime in the 17th or 18th Century, for reasons that are not clear. No sightings of the species had been made in the Atlantic Ocean since.

That was until a single individual gray whale was sighted off the coast of Herzliya Marina, Israel. On 9 May, researchers from the Israel Marine Mammal Research and Assistance Centre (IMMRAC) in Israel went to investigate.

They took photographs to identify the huge animal, which they have since confirmed is a gray whale. "This discovery is truly amazing. Today, gray whales only inhabit the Pacific Ocean, so to find one in the North Atlantic, let alone the Mediterranean Sea, is bizarre in the extreme," says Ms Nicola Hodgins of the Whale and Dolphin Conservation Society (WDCS), which is headquartered in London, UK.

Scientists baffled

The WDCS says that experts are baffled by the whale's appearance. "Gray whales are well known for performing one of the world's longest migrations, making a yearly round trip of 15,000-20,000 km," says Ms Hodgins. "Over a lifetime, a gray whale migrates the equivalent distance of a return trip to the moon.

"However, these new images show that this particular whale would have had to beat all previous distance records to end up where it has." It would also have had to swim a circuitous route to reach the Mediterranean, perhaps taking the extremely unlikely course of swimming up a major swimming canal that links the Pacific and Atlantic.

That raises the possibility that the whale did not swim into the Mediterranean Sea alone, but is part of a population that has recolonised parts of the Atlantic Ocean, and the Mediterranean Sea that links to it. "Its presence off the coast of Israel will certainly pose a lot of questions to the scientific community," says Ms Hodgins.

http://news.bbc.co.uk/earth/hi/earth_news/newsid_8672000/8672970.stm