Sloths have wiry grooved hairs that encourage the growth of blue-green algae. This gives them a greenish tint that helps them evade predators.
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aka Southern two-toed sloth or Unau
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
Where They Live
What They Do
How They’re Doing
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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.
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.
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.
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.
Sloths are unusual mammals. They are extremely slow moving and designed for a life hanging upside down in trees. Their limbs are modified so that the arms are longer than the legs and the narrow hands and feet terminate in long sickle-shaped claws. Fingers and toes are fused and reduced in number to two on the forelimbs and three on the hindlimbs (Toe-toed sloths) or three on all four limbs (Three-toed sloths). Sloths are nocturnal and solitary by nature, although several females may group together in one tree. The animals space themselves throughout the forest but do not defend territories.
Range and Habitat
Sloths have an unusually low metabolic rate allowing them to live on little food or poor quality food. They have a stomach that is divided into right and left halves, each of which is divided into several compartments. Because a sloth’s body temperature falls with the surrounding temperature, and proper digestion requires warmth, sloths take a long time to digest their food. Vegetation can be low in nutrition, and food may spend up to a month in the stomach so that the sloth can extract every bit of available nutrients. Sloths get needed moisture through juicy leaves and by licking dew drops or water collected inside bromeliads.
Adaptations and behavior