Fewer than 350 animals
Western Pacific grey whale. The most endangered of all great whales, and a potential victim of oil and gas exploitation off Sakhalin Island on the far east of Russia. Likely oil spills threaten the habitat of a population of as few as 120 individuals. The death of just three females could mean the extinction of the species.
Fewer than 120 animals
Bowhead. Once known as the common or Greenland whale, this cetacean was targeted by British whalers in the 18th and 19th centuries; William Scoresby of Whitby took 533 in his whaling career alone. The bowhead – a close relative of the right whale – is rarely seen as it confines itself to Arctic waters, using its huge head to break ice in order to breathe. It is threatened by the receding polar ice, and by the probable expansion of the oil industry.
Fewer than 120 animals
Narwhal. Another Arctic whale, its 10ft-long tusk – in fact, an overgrown tooth – is the source of the legendary unicorn's horn. (Medieval hunters and apothecaries conspired to create a market for its supposed properties as an antidote for poison and melancholia.) Named after the Norwegian for 'corpse whale', it is still hunted by aboriginal peoples, who can sell its ivory tusks for up to $7,000 a piece. It too is threatened by the shrinking north polar ice cap.
Fewer than 120 animals
Cook Inlet beluga whales. Named after the Russian for white, belugas are known as canaries of the sea for their vocal chirrups and whistles. Common in the Arctic and sub-Arctic waters, they are under threat from pollutants such as mercury