A LONG STRUGGLE to save the whales from extinction ended in success this week when the International Whaling Commission (IWC) approved a worldwide ban on whaling from the huge factory ships that can cruise for months at a time, killing and processing thousands of whales. Though not a total victory - the measure exempts the small Minke whale, which is still used for food in Japan, and landbased whaling is still allowed - the vote is still a grand achievement for conservation and for international cooperation in protecting global resources.

Unhappily, the IWC's action may have come too late for some of the species. It seems that by the time it becomes clear that a whale species is declining, there may be too few left to make a comeback. Scientists don't know exactly why this is so, thought the whales' long infancy, small number of offspring and wide range are thoughts to be key factors. But unlike many other animals, such as the American bison, which has made a spectacular comeback since being protected, whale populations have generally not recovered. The Atlantic grey whale, for example, has been protected for 50 years and is still commercially extinct. The Great Blue - everyone's mental image of this magnificant animal - has been protected since 1965 but has not made a recovery. Some other populations seem to be growing, but the only real success story is the Pacific grey whale, whose migration down the California coast each year attracts thousands of thrilled onlookers. This species was once hunted down to 800 individuals, but, under complete protection, now numbers 18,000. One can only hope that it is not too late for the others.

Credit for the ban belongs to many. The United States has been steady and persistent in working for at least a 10-year moratorium while scientists search for more information. Australia provided a big impetus this year by adopting a permanent ban on all whaling by Australians and urging a global ban. But the ban is mainly the result of a worldwide movement of organized private groups, who have worked diligently to save these great sea mammals and who have made the whale the symbol of all endangered and extinct species. Now that an international body has actually done what many thought impossible, maybe action can be taken more quickly to deal with the dozens of similar problems still on the international environmental agenda.