Scientific name: Choloepus didactylus
Country: Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela
Continent: South America
Diet: Leaves - folivore, fruits, frugivore, occasional insects. In the Zoo the diet is a salad of fruit and vegetables.
Food & feeding: Omnivore
Habitats: Tropical rainforest
Conservation status: Least Concern
Relatives: Three-toed sloth, giant anteater
Description: The two-toed sloth has a body weight of seven to nine kgs. It is usually brown in colour, ranging from light tan to dark brown, with lighter fur around the face and head. The under fur is dense, often matted, while the outer fur is finer and sleek. The hair flows back from the head and as the animal is almost constantly upside down, the body hair lies from belly to back so that the rain will run off. Often the fur has a greenish tinge caused by microscopic plants that live on the hairs. There are two claws on each fore foot and three on the hind feet. The fore claws may measure up to 7.5 cms. Sloths are actually much better at swimming than walking, using their strong fore feet to propel themselves through the water, although they spend almost all of their time in the trees.
Lifestyle: This unusual leaf-eating animal spends most of its solitary life hanging upside down from the forest canopy. It eats, sleeps, breeds and nurses its young in this position but will also sit in the fork of a tree. It always descends to the ground to pass urine and faeces and does this every three or four days. It will avoid going down to the ground on other occasions where it is at risk from predators such as jaguars and ocelots. Unlike most mammals, its body temperature varies considerably depending on the temperature of their surroundings. They have colour vision, a good sense of small and a poorly developed sense of hearing. The two-toed sloth is nocturnal, sleeping during the daytime and eating at night. They move very slowly at night, one limb at a time, at about 0.5 km per hour, but when sufficiently motivated they are capable of moving at about 1.6 km per hour. Swimming is an adaptation to the annual floods that occur in the forest.
Family & friends: Sloths are solitary, coming together only to mate.
Keeping in touch: Little is known about communication in this species.
Growing up: The gestation period is around 7-10 months. A single, well-developed young is born and is carried on the mother's body for six to nine months, hooking itself securely into her breast fur. By about one month it begins to take leaves chewed by the mother and after a further month it can pick its own leaves from those it can reach while hanging onto its mother's fur. It reaches adult size between two and three years old and can live for up to 30 years in captivity.
The body temperature of the two-toed sloth is amongst the most variable of any mammal, ranging from 24 to 33 degrees centigrade, depending on the weather and the time of day. By contrast, human body temperature is a stable 37 degrees centigrade, whatever the weather, unless we have a fever or are suffering from hypothermia. We would die if our body temperature dropped as low as a sloth.
Conservation news: Being so slow moving, sloths are unable to escape if an area of forest is felled for agriculture or timber. They are often killed during logging operations. Little is known about their total population, but the forest in which they prefer to live is under significant threat.