National Geographic : 2010 Jan
• larvae to feed, for one---and it takes at least eight months to grow them to marketable size. But the economics of wild clownfish have been changing: Rising fuel costs have made ship- ping them more expensive, and populations have been declining. Overharvesting and invasive col- lection methods, such as the use of cyanide to stun and capture sh, are destroying reefs and their inhabitants. In the Philippines and Indo- nesia, for instance, clown sh have been severely depleted. Loss of clownfish leaves anemones exposed and vulnerable to predation. When reefs go bad, one of the rst things to disappear is anemones---and their clown sh. " ey're a really good indicator group," Allen says. Besides spurring demand for clown sh, Find- ing Nemo helped fuel the explosion of websites and chat rooms devoted to raising reef sh in captivity. ORA breeds 13 clownfish species, as well as designer exotics such as the Picasso clown. Rado says he sells some 300,000 clown- sh a year---"that's several hundred thousand that won't be taken from the wild." Despite the reef degradation Allen has wit- nessed during his 40-year career, he says that in some areas "there's incredible hope. Many reefs are almost pristine and very healthy." His focus now, as a consultant for Conservation Interna- tional, is "to identify these areas and help with their preservation before it's too late." Although the movie may have harmed native populations, Stanton's colorful little character also created a new group of nature lovers, ea- ger to preserve clown sh and their reef homes. "I hope it increased awareness," Stanton says. "I know it's precarious out there." j parrot sh, change from female to male. But the clown sh is one of the few known to change from male to female: If a dominant female dies, the dominant male will become the dominant female, and the largest remaining juvenile will assume the role of dominant male. No one has yet identified the hormones responsible for this sexual plasticity. "It's a really good adaptive strategy to make sure the species is perpetuat- ed," Allen says. " ere will always be a breeding pair at any given anemone." and the anemone---their re- lationship has captivated home aquarists since the 1970s, when improvements in the shipping of sh and in tank design and ltration caused a boom. But never before has a sh had a bigger boost than the clown sh in the wake of Find- ing Nemo (unlike the notoriety of a very large mechanical killer with teeth). At first, fear spread through the aquarium industry that the story line would cause a backlash: Nemo is cap- tured and held in a tank in a dentist's o ce, and his father spends the rest of the time trying to rescue him. "I'm here to tell you the opposite happened," says Vince Rado of Oceans, Reefs and Aquariums (ORA), a hobby- sh hatchery and wholesaler in Fort Pierce, Florida, whose sales of A. ocellaris---a Nemo look-alike spe- cies---jumped by 25 percent. " ank God for little Nemo!" Stardom has been a mixed blessing for clown- sh themselves. For years it has cost much less to catch and ship wild-caught clown sh than to raise the sh in captivity. Breeding them in tanks presents certain challenges---getting the 0mi 1,500 0km SCALE AT EQUATOR 1,500 Clownfish range 150°W 30°E 90° 30°S 30°N TROPIC OF CANCER TROPIC OF CAPRICORN EQUATOR INDIAN OCEAN PACIFIC OCEAN Okinawa JAPAN PHILIPPINES MALDIVES SEYCHELLES INDONESIA FIJI ISLANDS PAPUA NEW GUINEA FRENCH POLYNESIA (FRANCE) AFRICA ASIA AUSTRALIA JEROME N. COOKSON AND LISA R. RITTER, NG STAFF SOURCE: GERALD ALLEN, WESTERN AUSTRALIAN MUSEUM CLOWNFISH RANGE Throughout the Indian Ocean and western Pacific, 29 clownfish species live symbiotically with 10 species of anemones. Degradation of some reef habitats threatens their survival.