Hoffmann's Two-toed Sloth

Choloepus hoffmani

Status in the Wild:

Common

Ancestors of present day sloths can be traced back in time about 60 million years. There were both tree sloths (present living species are all tree sloths) and ground sloths. Some species of ground sloth were the size of an elephant. The great majority of sloth species originated in South America, during the time when that continent was isolated from all other continents. Ground sloths reached their peak about eight million years ago. They radiated into the Caribbean and eastern United States including Florida. The ground sloths became extinct about 10,000 years ago.

There are two species of tree sloth in the two-toed family and three species of tree sloth in the three-toed family. A more accurate common name would be two or three-fingered sloths because all two-toed sloths have two fingers on the fore-foot and three toes on each hind foot. Three-toed sloths have three fingers on each fore-foot.

Range:

Central and South America from Nicaragua through Columbia and western Venezuela south to northeast Equador.

Habitat:

Tropical forests. They are highly arboreal, going to the ground only about once a week to urinate and defecate which they do in communal areas. The only other time they will go to the ground is to relocate to another tree not reachable from above ground.

When in the trees, sloths spend much of the time hanging by all fours upside down from a tree limb. They can do this because they are equipped with strong limbs with three to three and a half inch curved claws (toes) on each foot. Sloths move about, eat, sleep, copulate and give birth while hanging by four or two feet from tree limbs. All activity is done very slowly to minimize the expenditure of energy. They spend so much time upside down that they are the only mammals whose fur is parted and flows from belly to back. This allows run-off of water during rainstorms. Sloths are also the only mammals that can turn their heads about 180 degrees in both directions, an adaptation shared with only a few other groups of animals – owls and some prosimians.

Description:

Sloths are normally a light tan in color, but may be greenish in color in the wild due to the presence of one or two species of blue-green algae living in their fur. This provides additional protective coloration for the sloth. They can weigh up to twenty pounds and have a head and body length of about two and a half feet. Tails are very short and generally can’t be seen.

Diet:

Sloths appear to be strictly herbivores, feeding on leaves, young shoots, flowers and fruit. Due to the high cellulose content in their diet, sloths have very complex stomachs and a lengthy (in time) digestive process. It has been estimated that up to about one third of a sloth’s weight may be made up of stomach contents. Sloths do not over exert when eating. They just anchor themselves and start mulching. Since they do not have incisors, they tear off food using their tough lips.

Teeth: Sloths have primitive peg-like teeth. They do not have incisors or canine teeth. They have a total of ten upper and eight lower molars. These teeth lack enamel and grow continuously.

Body Temperature: Sloths can conserve their use of energy by adjusting their body temperature. Sloths have the most variable and lowest body temperature of any mammal. Their temperature can range from 76 to 96 degrees, dropping on cool nights, during rainy weather and when sloths are inactive. Their metabolic rate is about half of what might be expected of an animal of similar body weight.

Habits:

Sloths are nocturnal and are generally solitary. There are other adaptations for survival. Although they are completely at home in trees, sloths are not a picture of grace when walking on the ground. Their gate is slow and deliberate. Sloths can swim surprisingly well. They swim right-side up using a type of overhand stroke.

Predators:

Sloths are preyed upon by ocelots and jaguars, particularly when sloths are on or near the ground. Harpy eagles may take young sloths. When pressed, sloths can defend themselves effectively and vigorously with teeth and claws. Sloths have the ability to survive wounds and injuries that might be fatal to other mammals. Although sloths are rather abundant, they are not hunted much by native people because their habit, even after death, of continuing to cling to a tree limb.

Reproduction/Gestation:

Sexual maturity is reached at about three years in females and between four to five years in males. The young become independent from their mother at about one year. Weaning commences at about ten weeks. While caring for the young, Hoffmann’s females are very protective and attentive mothers. The gestation period is about 11 ½ months with a single sloth being born. Sloths in captivity can live over 30 years. The life span in the wild is closer to 12 to 16 years.