The sloths of Costa Rica

ESTRELLA RIVER, Costa Rica — Nimble and quick they are not. But there is something absolutely captivating about those big fur balls that appear too sleepy to budge from their home high up in the tree branches — barring weekly visits to the rest room down below for a No. 2.

“People can watch the sloths sleep for hours,” says Judy Avey — and she should know.

The 63-year-old Costa Rica resident (she’s originally from Anchorage, Alaska) has spent many hours studying these creatures, especially since 1992, when three local girls near the Caribbean coast hotel she owns with her husband spotted a three-month-old sloth in the road. The girls carried the orphan to the hotel in search of help, and thus began Avey’s study of this misunderstood mammal, which has become a favorite sight on the Costa Rica tourist trail.

The rescued sloth, which earned the named Buttercup, was the first of the nearly 400 sloths to come under the care of Avey, her husband Luis Arroyo, their daughter and grandchildren at their Aviarios Sloth Sanctuary of Costa Rica, just north of the Caribbean coastal town of Cahuita.

Many of the sloths, delivered by locals or travelers from up and down the country’s Caribbean coast, are just a few months old when they arrive, while others are injured adults. Sometimes they have been badly electrocuted after climbing electrial or telephone cables, or have been crippled by a bad fall.

Since early March, eight sloths belonging to the choloepus genus and six of the bradypus genus have arrived (these are the only types found in Costa Rica), according to Avey. The choloepus is commonly called a two-toed sloth, although Avey points out it’s more like two fingers, as the animal’s lower limbs each have three toes. The bradypus has three “fingers” and a sort of smiley face and appears to be wearing a mask around its eyes.

For both types of sloths, the fingers and toes are curved, claw-like bone appendages with fingernail coatings, which help sloths cling to branches and stuff a variety of tree leaves, such as beach almond, into their mouths. Sloths can also use the claws for defense against predators — such as jaguars, large snakes, harpy eagles — although the sluggish herbivores aren’t likely to ever be the first to attack. Their defense is further aided by an algae that grows within their furry coat and helps hide their scent from possible predators, such as ocelots, Avey says.

But it’s humans that have long been one of the sloths’ biggest threats.

What tourists find to be unusual, adorable creatures, some locals — who call them "osos perezosos," or lazy bears — have been known to treat like pests. Avey describes incidents when children have taunted and thrown rocks at the animals, even while adults stand by watching, saying, “let the kids have fun,” she says.

“It’s hard to say this but they’re an easy target because they can’t scamper away,” she says. “We’ve heard horrendous stories.”

In addition to rehabilitation, the rescue center seeks to prevent sloth abuse through education programs, including one with financial backing from the fruit company Dole, which buses in the children of its field workers for sloth classes at the center. Avey believes the programs are working and that “understanding of the sloth is improving.”

“We teach the children and the children teach their parents or their peers,” she says.

“I’m not lazy, I’m digesting”

Avey hopes to spread sloth knowledge beyond her local community — currently, six of the sanctuary’s sloths are on loan to the Dallas World Aquarium. Avey also intends to write a how-to book on sloth husbandry, to share the knowledge she has learned largely by trial and error.

She can start by explaining what makes sloths sleep all the time. Some reports say they can snooze for more than 15 hours at a stretch, although a scientific study suggests that, when in the wild, those spans of time are shorter.

Avey attributes it to the sluggish nature of sloth digestion, which involves moving food slowly through a large multi-chambered stomach. “My veterinarian calls them ruminants that don’t ruminate,” she says, referring to cud-chewing mammals like cattle, camels or deer.

Speaking for the sloth, she says, “my favorite saying is, ‘I’m not lazy, I’m digesting.’”

And who said a sloth never moved? Almost once a week, they climb down their tree for a bowel movement. During this time, moths living off the algae in the sloth’s fur fly off and lay eggs in the animal’s dung, only to later fly back up to the tree to find their host (a relationship that prompts Avey to recount a tongue twister about the “moth that lives on the sloth eating the sloth’s moss”).

Above all, Avey wants to set the record straight. “My husband says when Buttercup found us, she found a mouthpiece to talk about her kind," she says. Sloths had "a pretty bad press agent in the beginning when they were named after a deadly sin.”

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