It carries itself with classic elegance, a nine-foot-long torpedo with tapered fins. Like their oceangoing cousins, Caribbean reef sharks swim fast to force water through their mouths and over their gills so they can take in oxygen. But they can also ventilate their gills by using muscles in their mouth while lounging in the shallows, where they stalk reef-dwelling fish and the occasional unlucky lobster, says Brendan Talwar, a researcher with the Scripps Institution of Oceanography near San Diego, who has worked with Caribbean reef sharks off the island of Eleuthera in the Bahamas.

In fact, their iconic streamlined form belies a homebody nature: They rarely stray more than a handful of miles from the reefs they frequent in the Caribbean and along the Atlantic coast of South America. In unprotected waters, this makes them an easy target for fishers, who in the past sold their fins to Asia for soup and still locally sell their meat for food, their skin for leather and their liver for oil, which is a rich source of vitamin A. Since the 1980s, Caribbean reef shark populations have dropped 52 percent. In some places, their numbers have plummeted by as much as 99 percent, and since 2021 the sharks have been classified as endangered.

But their stay-at-home tendencies have an upside. Because the animals tend to hang out in the same places, dive operators can count on seeing them, and they’ve spawned a burgeoning dive ecotourism industry in the Caribbean. Descending underwater with a professional shark handler carrying a container of fish, recreational divers wait on the seafloor. Soon enough, a Caribbean reef shark—sometimes a shiver of sharks—emerges from the deep blue beyond, looping over the heads of the divers and claiming fish from the handler, who feeds the shark using a long metal stick.

Cristina Zenato, a shark behaviorist and dive instructor, sees the same “girls,” as she fondly calls them, month after month, and refers to them by their unique features. Vulcan has a pointy fin, Black Spot a black eye resembling a pirate patch around her right eye. An old-timer, Grandma, has been a regular for 13 years.

While feeding wildlife is widely discouraged because it can change animal behaviors—think bears in Yellowstone or deer in suburban backyards—research suggests that shark-diving tourism doesn’t much alter the behaviors of Caribbean reef sharks as long as it’s done responsibly, by controlling the amount of fish fed to the sharks. This approach, says Zenato, “doesn’t create co-dependence and it doesn’t create disruption of their natural behaviors.”

The Bahamas outlawed longline fishing in the 1990s and designated a shark sanctuary in 2011. As a result, populations have stabilized, and shark encounters now generate around $110 million for the Bahamas annually. The hope is that shark ecotourism can provide a lifeline to locals who depend on the sea for their livelihood. “It gives reef sharks a value for being alive that’s far greater than being dead,” Talwar says.

Cover image of the Smithsonian Magazine September/October 2023 issue

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