I am not a morning person, but I’m on a motorboat at 8:30 a.m., en route to a patch of the Caribbean more than an hour’s ride from Cancun, Mexico, scanning the waves for fins. Whale sharks are early risers, literally — they spend their mornings feeding on plankton near the surface, and if you come late, you’re likely to miss them. Otherwise, they’re pretty easy to spot.

 

Ranging in size from 35 to 50 feet long, with distinctive dotted flesh that has earned them the nickname Domino, whale sharks (Latin name: Rhincodon Typus), known locally as tiburones de ballena, are as awe-inspiring as you’d expect the world’s largest fish to be but far less fearsome than their more predatory cousins. Fortunately for us, they don’t shy away from humans sporting snorkel gear who’ve converged on their habitat in 30 boats for the chance to swim with them.

 

As we take our turns in the water with our guide, Diego, around a half dozen of the gentle giants surround us, close enough to touch — though that’s not permitted. It’s a special experience, and it’s not surprising that the whale shark swim has become a popular tourist activity, boosting the economy and providing a new career option for local fisherman, giving Mexico even more incentive to invest in conservation of the species. 

 

Isla Mujeres, an island off the coast of Cancun closer to the whale sharks’ feeding grounds, celebrates the species with the Whale Shark Festival every July, featuring a parade, carnival, and a conference dedicated to scientific research and conservation. According to marine biologist Rafael de la Parra, coordinator of Project Domino, whale sharks travel solo, but can congregate in pods of up to 400 individuals when food is plentiful. They’re in season off Isla Mujeres between late May and September, and the rest of the year “travel through the Atlantic making the shape of the number 8, looking for banks of food.”

 

While they’re not considered endangered, and populations are stable in North America, whale sharks face their biggest threat from humans — and the propellers of boats.

 

Designated “indeterminate” status on the World Conservation Union’s Red List of Threatened Animals for lack of data, and “vulnerable” by the International Union for Conservation of Nature and Natural resources, they’re at risk in Asian waters as they’re hunted for food in countries like Taiwan and the Philippines. Their large size, slow growth, late maturation and long lives — they can live between 60 and 100+ years — make whale shark populations slow to recover from overfishing. Promisingly, there is pending legislation in the Maldives and the Philippines that would ban whale shark fishing.