In 1966, at the end of the commercial whaling era, humpback whales in the North Pacific numbered only 1400. But now thanks to the international whaling ban, researchers say there are at least 21,000 humpbacks , and possibly even more, according to numbers reported in this month's Marine Mammal Science. The whales were counted during a special 3-year project, known as Structure of Populations, Levels of Abundance and Status of Humpbacks (SPLASH), which was launched in 2004. An international team of hundreds of scientists photographed more than 18,000 humpback whale tails, or flukes, from Alaska to Guatemala and from the Philippines to Russia. Each humpback's fluke is as unique as a human's fingerprint, and bears a one-of-a-kind pigmentation pattern. Researchers determined the whales' current population numbers by comparing photographic shots of humpbacks in their North Pacific feeding grounds (around the Pacific Rim from California to Kamchatka) to images taken of the whales in their southern, tropical breeding areas—some as far as 3000 miles away. They derived the 21,000 figure via further statistical analysis of the photographic data. The humpbacks' strong numbers show that they have largely recovered from whaling, though it will still take some time for them to reach their estimated historical number of 125,000 individuals worldwide.
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