Bonn, Germany -- Melting ice caps due to global warming could lead to extinction of Antarctic blue whales by eliminating their main food supply, World Wildlife Fund warned today.
Sea ice provides a habitat for microscopic marine algae, which are released in the summer when the ice melts and are fed upon by krill, the main food supply for blue whales. Several studies have shown that as the temperature has increased in recent decades, sea ice has diminished rapidly and thus food supplies for krill are getting scarce. A 2001 study on krill-eating predators in South Georgia published by the British Royal Society found that population size and reproductive performance were declining in all species. They concluded that the biomass of krill was insufficient to support predator demand in the 1990s and that the demand for krill now exceeds supply.
"WWF is calling on governments meeting at the Climate Summit in Bonn and the International Whaling Commission in London to take action to ensure a future for blue whales," said Cassandra Phillips, WWF's Senior Policy Advisor on Whales and the Antarctic. "The world's largest problem, global warming, could mean extinction in the Antarctic for the world's largest animal."
The blue whale population in the Antarctic was drastically reduced by commercial whaling, from 250,000 a century ago to probably below 1000 today. The population has shown no signs of recovery since blue whales were officially protected from whaling more than 35 years ago. Despite the ban on hunting blue whales since 1965, some whaling continued until the 1970's by Soviet factory ships. In 1994 it was revealed that 1433 blue whales had been killed since the ban and the Soviets had falsified their records, reporting a catch of 156. Since then, there is no evidence that their numbers have started to recover and any slight impact on their remaining population could mean extinction in the Southern Ocean.
Compounding the threat of climate change to krill populations is the interest shown by several countries to enlarge the commercial krill fishery, possibly to unsustainable levels. This activity could be the final nail in the coffin of the blue whale. With less than a week to go before the opening of the International Whaling Commission meeting in London, WWF is calling on the IWC to provide funding for long term population surveys and undertake research on the links between blue whales, krill and climate change.
"This is a creature of prehistoric proportions, but living in today's world. Despite the best efforts of the whalers the Antarctic blue whale still survives, yet its fate is once again in the hands of a few nations who have only their own interests at heart. This time the world is watching," said Stuart Chapman, Head of WWF's Species Programme.