ANTARCTIC minke whales were much more abundant before whaling began than previous estimates suggest. That鈥檚 according to genetic analysis of whale meat bought in Japanese grocery stores. The finding makes Japan鈥檚 assertion that increasing catches will not endanger the minke less tenable than ever.
The DNA survey by marine biologist Steve Palumbi of Stanford University鈥檚 Hopkins Marine Station in California reveals that the species is the most genetically diverse of any whale. It suggests that the population was once between 500,000 and 1 million individuals. This is vastly higher than other estimates, some of which are as low as 20,000.
Japan claims that today鈥檚 population of around 760,000 minkes (Balaenoptera bonaerensis) is abnormally high and so threatens the recovery of other endangered species, such as the blue whale, by competing for food. Japanese delegates at the International Whaling Commission have used this argument to support their calls for the resumption of commercial minke whaling.
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Most estimates of historic whale population size are based on figures from whalers鈥� log books, but Palumbi argues that logs may be incomplete or deliberately inaccurate and points out that records do not include mortally wounded whales that escaped.
Palumbi announced his results at the American Association for the Advancement of Science meeting in Washington DC. He arrived at his estimate by looking at two genetic regions in mitochondrial DNA, which passes down the maternal line. High genetic diversity in the population indicates past abundance of the species, because small populations lose diversity through inbreeding.
鈥淭here is no evidence whatsoever that their population growth is inhibiting populations of other whales in Antarctica,鈥� he told 快猫短视频. His study, which builds on earlier data (快猫短视频, 2 August 2003, p 4), also reveals that Antarctic minke whales may be the oldest surviving whale population on Earth. Palumbi was able to extrapolate their origin back one million years to a single minke 鈥渕itochondrial Eve鈥�.
