Mammoth black-and-white Killer Whales, the mammals made popular by films such as Free Willy, face the terrible danger of extinction in the seas around Europe.
The cause of the problem is of human origin – poisonous chemicals.
Like other animals at the top of the food chain, the Killer Whale is particularly at risk of poisoning from accumulation of toxins, including polychlorinated biphenyls (PCBs) and a new study is reporting that high levels of PCBs are still being pumped into the world’s oceans.
And that despite it being banned many years ago.
The report of the study, of 1,000 Killer Whale, Dolphin and Porpoise samples taken off the Strait of Gibraltar, Spain’s Canary Islands, Britain and Ireland, describes the Strait of Gibraltar, their only passage between the Atlantic and the Mediterranean, as being ‘especially bad’.
The findings of the study, published in Nature magazine, have prompted zoologists to now call for tougher regulations including more stringent penalties for those caught disposing of man-made PCBs into the seas.
Paul Jepson, speaking on behalf of the London-based Zoological Society, said: “It’s really looking bleak. We think there is a very high extinction risk for Killer Whales as a species in industrialised regions of Europe.”
An earlier survey, off Washington state’s Pacific coast, found PCB levels in Killer Whales were higher than levels that had caused health problems in harbour seals. Meanwhile whale blubber samples in the Norwegian Arctic have been found to show higher levels of PCBs, pesticides and brominated flame-retardants than in polar bears.
More properly known by its latin name Orcinus orca, the Killer Whale is also referred to as the Orca. It is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. There are four types of Killer Whales that, between them, are found in all oceans.
They have a varied diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals like seals, and even large whales. They have been known to attack baleen whale calves. Killer Whales are regarded as apex predators residing at the top of a food chain – upon which no other creatures prey or one lacking natural predators.
Killer whales are highly social; some populations are composed of matrilineal, or female line, family groups which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviour, or ‘whale song’, are often specific to a particular group and passed across generations and have been described as manifestations of culture.