The study is a collaboration of three dozen of the world’s top whale shark experts and thousands of citizen-scientists — mostly snorkeling ecotourists who snap photographs and video as they swim alongside the behemoths. PhotoA scientist or tourist can take a picture or video of a whale shark — ideally from its left side — then upload the image to www.whaleshark.org. Whale sharks were declared endangered last year after their numbers apparently dwindled. The juvenile males don’t appear to migrate much, Dr. Norman said, with many seen repeatedly in the same region, and not much mixing across the hot spots. Worldwide, estimates of the population range from about 20,000 to about 200,000 whale sharks, Dr. Dulvy said.

Source: New York Times November 29, 2017 17:15 UTC