The humpback whale, nearly hunted into history four decades ago, was now on the ''road to recovery'' and no longer considered at high risk of extinction, an environmental group said yesterday.
The International Union for Conservation of Nature, which produces a ''red list'' of threatened species each year, also upgraded the status of the southern right whale from vulnerable.
An expert on marine mammals for the conservation organisation, Randall Reeves, said, ''Humpbacks and southern right whales are making a comeback in much of their range mainly because they have been protected from commercial hunting. This is a great conservation success and clearly shows what needs to be done to ensure these ocean giants survive.''
Another expert at the group, Bill Perrin, said the humpback whale population had dropped to the ''low thousands'' when it was finally banned from commercial hunts in 1966. Its numbers had since risen to at least 60,000, he said, adding that the population was increasing at a healthy rate of 5 per cent each year in the North Pacific.
While the right whales that hug the southern coasts of Argentina, South Africa and Australia are also recuperating, their cousins in the north are struggling.
Dr Perrin said there might be only 300 North Atlantic right whales along the US eastern seaboard. While hunting them was illegal, many continued to be wounded or killed in collisions with ships or entanglements with fishing gear.
The International Union said a number of other large sea animals were moving closer to extinction. Overall, nearly a quarter of all such species were threatened and more than a 10th listed as endangered or critically endangered, representing the greatest threat of extinction.
The Irrawaddy dolphin of South-East Asia, the finless porpoise that swims from the Persian Gulf to the coast of north Japan, and South America's franciscana dolphin are all considered vulnerable largely because they are often a bycatch in fisheries.
In Mexico's Gulf of California, the vaquita porpoise will probably be the next animal of this type to become extinct. Already critically endangered, about 15 per cent of those remaining were killed each year in gill nets, the organisation said. It estimated that only 150 were left in the wild.
Noting the decline in hunts of whales and other sea mammals over the past few decades, the International Union said accidental killing in fishing gear was now the ''main threat'' to these species.
Those being particularly hard hit also include the Black Sea harbour porpoise and the western grey whale. AP