Sloths are slow-moving mammals found exclusively in the tropical forests of Central and South America. They spend almost their entire lives suspended from trees, relying on the dense canopy for food, shelter, and protection. This arboreal existence requires a specific geographical and environmental range that provides consistent resources and an interconnected network of branches. Their distribution is separated into two distinct families, each occupying slightly different niches across the neotropical region.
The Distribution of Two-Toed and Three-Toed Sloths
The six living species of sloth are divided into two genera: the three-toed sloths (Bradypus) and the two-toed sloths (Choloepus). The brown-throated three-toed sloth (Bradypus variegatus) is the most widespread species, extending from Honduras through Central America, including Costa Rica and Panama, and continuing into northern South America as far as northern Argentina and Peru.
The other three species of three-toed sloths have more restricted distributions. The pale-throated sloth (Bradypus tridactylus) is limited to the northern portion of South America, primarily within the Guiana Shield countries of Guyana, Suriname, French Guiana, and parts of Venezuela and Brazil north of the Amazon River. Conversely, the maned sloth (Bradypus torquatus) is endemic to a small, highly fragmented area of the Atlantic coastal rainforest in southeastern Brazil. The pygmy three-toed sloth (Bradypus pygmaeus) exists only on the tiny Isla Escudo de Veraguas, a Panamanian island measuring about 4.3 square kilometers.
The two-toed sloths are represented by two species, both of which have extensive ranges. Hoffmann’s two-toed sloth (Choloepus hoffmanni) has a fragmented distribution split by the Andes Mountains, with one population extending from eastern Honduras through Central America to western Ecuador. A separate population is found in parts of western Brazil, eastern Peru, and northern Bolivia. Linnaeus’s two-toed sloth (Choloepus didactylus) occupies a parallel range across northern South America, inhabiting Venezuela, the Guianas, Colombia, Ecuador, Peru, and Brazil north of the Amazon River. Both two-toed species demonstrate a high tolerance for varied elevation, found from sea level up to altitudes of 10,800 feet.
Specialized Tropical Canopy Environments
The sloth’s habitat is defined by specific environmental conditions found within tropical forests, requiring a dense, interconnected forest canopy. This high canopy connectivity, where branches and vines link trees, allows sloths to travel without descending to the forest floor.
These mammals thrive in ecosystems like lowland tropical rainforests, cloud forests, and mangrove swamps, all characterized by consistent warmth and high humidity. The optimal habitat typically receives over 250 centimeters of rainfall annually, which supports the lush foliage they consume. Sloths are heterothermic, meaning their body temperature fluctuates with the environment, making them highly sensitive to temperature drops.
They generally inhabit low-altitude areas, typically below 6,000 feet, where the thermal environment is stable and warm. Within the forest, they prefer the upper layers, which are rich in leaves and receive more sunlight for thermoregulation. The dense foliage and the algae that grow on their fur provide effective camouflage against predators like the harpy eagle. A wide variety of tree species is also necessary because sloths, particularly the three-toed species, have very selective diets composed of leaves from a limited number of plant types.
Conservation Status and Range Shrinkage
The geographical and environmental range of sloths is under constant threat, leading to a measurable shrinkage and fragmentation of their available habitat. The primary driver of this decline is deforestation, as tropical forests are cleared for logging, cattle ranching, and agricultural expansion.
Urbanization and road development further fragment the remaining forested areas, which isolates sloth populations. When the canopy is broken, sloths are forced to descend to the ground to cross open spaces, making them vulnerable to vehicle strikes, domestic dog attacks, and poaching. This fragmentation also leads to sloths using power lines to move, resulting in frequent electrocutions, which account for a high percentage of sloth deaths in some areas like Costa Rica.
The isolation of populations restricts the movement of individual sloths and prevents the mixing of genetic material, which can lead to genetic bottlenecks and reduced resilience to disease. Species with naturally restricted ranges, like the maned sloth in Brazil’s Atlantic Forest and the critically endangered pygmy three-toed sloth, are especially vulnerable to this habitat loss.