Sloths spend their lives hanging upside down in treetops by the sickle-shaped claws of their four limbs. Sometimes called the slowest animals on earth, bit by bit they move deliberately along branches, conserving energy and avoiding detection from predators.
What They Eat
Sloths feed primarily on vegetation—leaves, small twigs, berries, flowers, and fruit-and occasionally insects and small prey. Food is digested slowly and remains in the stomach for as long as one month.
Where They Live
Found in the coastal and mountainous tropical forests of Central America and northern South America, sloths live high in the forest canopy.
What They Do
Sloths sleep, eat, mate, and give birth hanging upside down in a tree. They descend from a tree every 4-8 days to urinate and defecate at the base. Excellent swimmers, sloths will take to the water during the wet season to change trees in search of food.
How They’re Doing
Some species of sloths are stable, while others are endangered. Threats to populations include habitat destruction and hunting for their meat, fur, and claws. Because of their slow nature, sloths are also frequently hit by cars in places where roads have been cut through the forest.
- With weak hind legs and bodies designed for a life upside down in trees, sloths are basically unable to walk when on the ground. Instead, they crawl slowly along the ground, usually from one tree to another.
- Sloths have wiry grooved hairs that encourage the growth of blue-green algae. This gives them a greenish tint that helps them evade predators.
- Because of their slow metabolism, sloths only need to defecate and urinate every 4-8 days and may lose up to 30% of their body weight when they do.
- The hair on their belly parts down the middle. This directs water away from their bodies while hanging upside down in the rain.
- Less muscle means sloths are lighter than most animals their size. This allows them to climb high in the forest canopy, closer to food and farther from large predators.
- Sloths’ body temperature changes with the temperature of their surroundings, and can vary as much as 10º F in 24 hours. For most animals, including humans, this would be life-threatening.
There are six species of sloth. The Brazilian three-toed sloth is endangered in its entire range. Exact population numbers are unknown for the Linne’s two-toed sloth. Threats to sloths include pesticides, deforestation, and power lines. Their continued survival depends on protecting their rainforest habitats.
Large numbers of toe-toed sloths still exist in the wild, but their habitat continues to be destroyed. Sloths are hunted for their lean meat, which is similar to mutton in flavor. Their straw-like fur is popular for use as saddlecloths and native people use their claws for necklaces.
Things the Zoo's done/doing
Aviarios del Caribe, the only sloth rescue, research, and rehabilitation center in Central America, has rehabilitated and released over 40 sloths. Adult sloths with permanent disabilities are kept at the center for scientific behavioral research, observation of their natural history, and environmental education.
When Aviarios needed to update and expand their educational curriculum in 2005, Melanie Sorensen, Minnesota Zoo Education Interpretive Naturalist, volunteered to spend a month in Costa Rica to help. While there she wrote curriculum, cared for sloths, led center tours, and assisted with the Costa Rican Environmental Education Program. The Minnesota Zoo provided Melanie with financial support to cover her travel costs and buy much needed supplies for the center.
After word got out about Melanie’s experiences in Costa Rica, keepers from around the country began to contact her with questions about their sloths. As a result, the Minnesota Zoo held the first ever “sloth symposium” in 2008. Keepers from around the country were invited to come together at the zoo to exchange information on sloths and put together a comprehensive manual on their care.