The six different species of sloth inhabit the same sort of environment -- the tropical forests of South America -- and display similar behavior. Perhaps surprisingly for rainforest creatures, only one sloth is in imminent danger of extinction. The other five are coping, although they are vulnerable to the continuous destruction of their habitat.
Pygmy Three-Toed Sloth
The critically endangered pygmy three-toed sloth (Bradypus pygmaeus) -- the tiniest sloth -- faces serious problems, mainly because of its extremely restricted range, which consists of one small island in Panama: Isla Escudo de Veragua. The species appears to eat nothing but the leaves of mangrove trees, which are being rapidly destroyed despite the island’s status as a nature reserve.
Distinguished by a circle of long dark hair around the neck, the maned sloth (Bradypus torquatus) is now limited to wet forests in eastern Brazil, although it probably had a wider range in the past. Although not as urgently threatened as the pygmy sloth, this species is still vulnerable because of its small, restricted range.
In contrast, the pale-throated sloth (Bradypus tridactylus) has a range extending through five countries -- French Guiana, Suriname, Guyana, Brazil and Venezuela -- and populations appear to be healthy at the moment. This sloth stands out because of the panda-like markings on its face -- dark patches around the eyes and mouth contrasting against a pale background.
Bolivian Three-Toed Sloth
The Bolivian three-toed sloth (Bradypus variegatus) also has a wide range as, despite its name, it is not confined to Bolivia. In fact, the species is found in at least 10 South American countries, including Peru, Ecuador and Costa Rica. Overall the species is fine, although some individual populations are threatened by habitat destruction and hunting.
Linne's Two-Toed Sloth
Another species with a wide range, Linne’s two-toed sloth (Choloepus didactylus) occupies the wet tropical forests of at least eight countries. As a solitary and well-camouflaged species that stays high up in the canopy, it's not an easy target for human hunters, or any other ground-based predator, and the species is in no trouble at the moment.
Hoffmann's Two-Toed Sloth
Hoffmann’s two-toed sloth (Choloepus hoffmanni) is widespread and relatively plentiful, but it is facing growing threats of habitat destruction, hunting and increasing capture for the exotic pet trade. This sloth’s habit of venturing onto farmland makes it easier for people to capture the animal.
- Animal Diversity Web: Pilosa -- Sloths and Anteaters
- The IUCN Red List of Threatened Species: Bradypus pygmaeus -- Pygmy Three-Toed Sloth
- The IUCN Red List of Threatened Species: Bradypus torquatus -- Maned Sloth
- The IUCN Red List of Threatened Species: Bradypus tridactylus -- Pale-Throated Sloth
- The IUCN Red List of Threatened Species: Bradypus variegatus -- Bolivian Three-Toed Sloth
- The IUCN Red List of Threatened Species: Choloepus didactylus -- Linne's Two-Toed Sloth
- The IUCN Red List of Threatened Species: Choloepus hoffmanni -- Hoffmann's Two-Toed Sloth
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