Southern right whales are making a comeback, giving ecologists a rare piece of good marine news as fish stocks shrink and oil spills foul fragile coasts.
South African scientists say an annual count has revealed the biggest number yet in the survey's 32-year history of the gentle giants, which can attain
lengths of 17m and weigh up to 70 tonnes.
Scientists from the University of Pretoria's Mammal Research Institute spotted 845 right whales during a seven-day aerial survey off South Africa's south coast last month, 169 more than last year.
"We are very happy we're getting this rate of increase," said institute scientist Dr Peter Best. "People are very pessimistic about whales in general. There are more [now] than there have been for 150 years."
Right whales each have a distinctive pattern of wart-like callosities on their heads by which they are identified.
Found in the Southern Hemisphere's subtropical and sub-antarctic waters, they faced extinction in the 1930s due to large-scale whaling.
In fact, they were so-named because whalers regarded them as the "right" whale to kill because they moved slowly and obligingly floated to the surface when killed by harpoons.
By the 1930s, uncontrolled whaling by American, British and French whalers had reduced the southern right population off South Africa's coast to between 100 and 200.
They have been protected since 1935 and are now believed to number in the thousands.
In winter they migrate to their southern breeding grounds, off Australia, South America and South Africa, from their summer eating grounds near Antarctica.
This year New Zealand imposed marine-reserve status on the remote Auckland Islands, 460km south of Stewart Island, because southern right whales and sealions are slowly rebuilding their numbers in the islands' waters.
The northern right whale has not fared as well as its southern cousin and is believed to number only around 300.
The northern right's woes stem from the fact that its annual migration route between the Caribbean and the rich feeding waters off Nova Scotia is also a busy shipping lane. Many die in collisions with ships.
- REUTERS
All about whales
Southern Right Whales
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