Panama's Swimming Pygmy Sloths Take to the Sea

It’s not easy being the slowest mammal in the world. While a cheetah can go from 0 to 60 mph in only three seconds, it takes a sloth all day to cover 41 yards. Sloths are r-e-a-l-l-y slow. But in the turquoise waters off the coast of Panama, a group of pygmy three-toed sloths has found an alternative mode—of transportation: Swimming!

“If they have to change trees, they just plop into the water,” says Becky Cliffe, a British zoologist and founder of the Sloth Conservation Foundation. “They’d rather swim than crawl on the ground.”

Discovered in 2001, these compact cuties (Bradypus pygmaeus) are found only on a small island 10 miles from the mainland. And while they’re not the only sloths to swim, they are the only sloths known to swim in seawater. In addition, writes Hillary Rosner at bioGraphic “These diminutive tree-dwellers seem to swim far more frequently than their larger cousins, placidly paddling with just their flat-snouted, hairy heads protruding from the turquoise sea."

As it turns out, the sloths’ diet of leaves leads to the generation of gas during digestion, which means “they’re like big balls of air,” Cliffe says. Fortunately, this makes them relatively buoyant and makes swimming easy. In fact, they can swim three times faster than they can move through the trees.

How amazing to see these dedicated canopy dwellers take to the sea. They may be slow by nature, but they've found a way to game the system.

All of the photos here come to us via the wonderful bioGraphic and were taken by Suzi Eszterhas, an award-winning wildlife photographer and conservationist. (If you love these photos—and how could you not?—look for her book, “Sloths: Life in the Slow Lane.”)

A mother pygmy three-toed sloth carries her three-month-old baby through the trees.

In their Caribbean home, pygmy sloths frequently paddle their way from one tree to another in the mangrove forests. Moving faster in the water than on the ground makes swimming the preferred mode of travel.

Since pygmy sloths are particularly vulnerable on the ground, they prefer to travel by the water or through the trees, like the one shown here.

When they swim, they keep just their heads above water ... because sloth-paddling is the new dog-paddling!