Class: Mammalia – mammals
Order: Pilosa — group of placental mammals found in the Americas, including anteaters and sloths, and extinct ground sloths
Family: Megalonychidae – two-toed sloths
Genus: Choloepus – two-toed sloths
Species: Choloepus didactylus – southern two-toed sloth, Linnaeus's two-toed sloth, Linné's two-toed sloth
Species: Choloepus hoffmanni – Hoffmann's two-toed sloth
4 to 9 kg (9 to 20 lb)
540 to 740 mm (21 to 29 in)
23 ± 7 mm (about 1 inch) (C. didactylus)
C. didactylus is uniformly brown. C. hoffmanni is lighter in color; pale throat, darker chest.
Gray-brown/tan hair during dry season. Tinted green in the wet season due to algal growth.
Choloepus didactylus: northern South America (Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela)
Choloepus hoffmanni: 2 separate populations—(1) Nicaragua, south to Venezuela and (2) northcentral Brazil, south to central Bolivia
Tropical and cloud forests with tree crowns connected for tree-to-tree movement
Least Concern (both species)
Choloepus didactylus: not listed (as of Oct 2019) (UNEP 2019)
Choloepus hoffmanni: Appendix III (UNEP 2019)
Populations in the Wild
Total populations not reported; see IUCN fact sheets for densities.
Population trends unknown.
Slow, deliberate movement. Agile in trees; move by hooking claws onto branches. Can move on the ground, but can only drag themselves with claws and forelimbs for short distances. Excellent swimmers.
Nocturnal; activity begins about one hour following sunset and ceases about two hours before dawn.
Adults typically solitary, unless with mates or young. Females may feed in same tree.
Mainly plants—leaves, twigs, buds, fruit. Occassionally small mammals (rodents) and insects.
Preyed upon by Harpy Eagles, anacondas, jaguars, ocelots, and humans
Females: approximately 3 years of age
Males: approximately 4-5 years of age
340-400 g (about 12-14 oz)
Age at Independence
10-12 months, but may remain with mother up to 2 years; weaned at about one month
In the wild: 10-15 years old
In managed care: over 30 years old
- In prehistoric times, sloths were found in the Americas (South, Central, and North Americas), the Caribbean, and Antarctica.
- Two-toed sloths do everything hanging upside down—eating, sleeping, mating and even giving birth!
- Unlike most mammals, a sloth's body temperature varies with temperature of environment; fur insulates; moving between sun and shade allows them to regulate their body temperature
- Four-chambered stomach is filled with bacteria, which helps ferment plant matter consumed
- Excellent camouflage and slow movements help them elude predators
- By eliminating waste near the base of trees, sloth fertilize the trees they live in
- Entirely dependent on forests; losing habitat to ranching, agriculture, loggind, and urban expansion
- San Diego Zoo Globals newest two-toed sloth born April 19, 2019 to mom Xena.