Diving with manatees in Mexico's unexplored caves

IN A flooded cave system in the Mexican state of Quintana Roo, on the Yucatán peninsula, a manatee mother (pictured above) swims up to cave diver Klaus Thymann, who captured stunning images of these endangered mammals living in a unique, under-explored habitat. “Of course, I think she’s looking at me,” says Thymann. “But the reality is she’s probably looking at the reflection in the camera.”

Carved into limestone rock by flowing water, the cave system, thought to be up to 16,000 kilometres long, links the coast with inland cenotes, freshwater-filled sinkholes created when cave roofs collapse. Thymann and his fellow divers have been exploring this system (pictured above) to film manatees, which, unlike the humans, navigate the passages with ease.

The manatees have probably been in the region for generations, says Thymann, yet there are estimated to be fewer than 250 of them in the Mexican Caribbean. Thymann is concerned that construction projects nearby are putting the area’s aquatic species at risk. A new train line will bring even more development to the popular tourist destination (pictured above). Construction can block the flow of water in the system, starving it of oxygen and potentially trapping manatees. Wastewater from surface run-off and sewage systems lowers the water quality in the area’s aquifer.

Though the coastal area is a protected manatee sanctuary, this doesn’t extend inland, where these manatees were photographed. So, while finding manatees within a relatively untouched cave network is positive news, these habitats may not remain so pristine for much longer.

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