Conflicting Situation
Sloths are known to be arboreal, i.e., tree dwelling, and therefore, the fact that ground sloths and aquatic sloths roamed the Earth at one point of time is bound to come as a surprise for most people.
Sloths are medium-sized mammals native to Central and South America, which are known for their characteristic slow movement. The three-toed sloths, for instance, move at a maximum speed of 2 m/min. More importantly, sloths only move when it is necessary. It is this slow movement―bordering on laziness―that has earned the species their common name.
There are six extant species of sloths, namely the pygmy three-toed sloth, maned three-toed sloth, pale-throated sloth, and brown-throated sloth belonging to the genus
Bradypus (three-toed sloths) and the Hoffmann's two-toed sloth and Linnaeus's two-toed sloth belonging to the genus
Choloepus (two-toed sloths). All these species are arboreal, i.e., tree dwelling. The closest relatives of sloths are anteaters.
Are Sloths Endangered?
Of the six extant species, one is enlisted as critically endangered, while one is enlisted as a vulnerable species by the International Union for Conservation of Nature (IUCN). On the other hand, the remaining four types are enlisted as least concerned species. It's difficult to notice these slow-moving arboreal animals in the dense forests of Central and South America, which, in turn, makes it difficult to study their population. Below, we will look at each of these sloth species individually and explain why they are becoming endangered.
CONSERVATION STATUS OF SLOTHS
Pygmy Three-toed Sloth
Critically Endangered
The pygmy three-toed sloth (
Bradypus pygmaeus) is a small sloth endemic to Isla Escudo de Veraguas, off the coast of Panama. It is typically found in mangroves on this island. One of the rarest mammals in the world, the pygmy sloth was scientifically described only in 2001. Despite the fact that it has no known predators, the population of this sloth species has always been low; courtesy, its restricted range. In 2011 though, a study revealed that there were only 79 pygmy three-toed sloths in the wild, which was much lower than what was estimated.
Threats: The major threat to the pygmy three-toed sloth is habitat destruction. Though the island is largely uninhabited, lumbering is rampant in this area. The resultant habitat fragmentation and habitat loss makes it difficult for this sloth species to breed. Inbreeding is yet another issue that threatens its future. Experts are afraid that inbreeding will reduce the level of genetic diversity in this three-toed sloth species, eventually leading to its extinction.
Maned Three-toed Sloth
Vulnerable
The maned three-toed sloth or maned sloth (
Bradypus torquatus) is a sloth species endemic to Brazil, named so because of its distinct pelage. The species was enlisted as an endangered species in 2008, but eventually in 2009, it was moved to the vulnerable list. The present-day geographic range of the maned three-toed sloth is restricted to the Atlantic coastal rainforest of southeastern Brazil, which makes things worse, because the Atlantic rainforest in itself has been reduced to less than ten percent of its original size.
Threats: The loss of habitat for this species can be attributed to human activities, such as lumbering and clearance of land for plantations. Besides habitat destruction, this sloth species also bears the brunt of subsistence hunting. It is not purposely hunted for food, but if the locals do come across it, they don't hesitate to kill and eat it. Though rare, the chances of this species being run over by vehicles do exist. Deforestation in the Atlantic forest has declined, but not yet stopped, and as long as such blatant killing of trees continues, it will continue to reflect on animals inhabiting this forest.
Brown-throated Sloth
Least Concern
The brown-throated sloth (
Bradypus variegatus) is considered the most widespread and common species in its genus. Its geographic range spans the forests of South and Central America. Even though it is enlisted as a least concern species by the IUCN, the brown-throated sloth has been at the receiving end of human activities.
Threats: It is mainly threatened by deforestation and resultant habitat fragmentation. Besides that, brown-throated sloths are also hunted for food, medicine, and to fuel illegal pet trade.
Pale-throated Sloth
Least Concern
Like the brown-throated sloth, even the pale-throated sloth (
Bradypus tridactylus) boasts of a widespread range. The similarity in their appearance often results in confusion between these two species. It inhabits tropical forests of various South American nations, right from Guyana to Brazil.
Threats: The species has no major threats in the wild. Though the locals are known to hunt it for food, such incidents are rare.
Hoffmann's Two-toed Sloth
Least Concern
The Hoffmann's two-toed sloth (
Choloepus hoffmanni) is found in Central and South America. It is named after renowned German naturalist, Karl Hoffmann.
Threats: This species bears the brunt of both, habitat degradation and habitat fragmentation. Additionally, it is also hunted for food and sold in pet trade. Despite these threats, this two-toed sloth has been able to hold its ground in its native habitat.
Linnaeus's Two-toed Sloth
Least Concern
And lastly, we have the Linnaeus's two-toed sloth (
Choloepus didactylus). The geographic range of this species spans dense forests of northern South America, in countries like Venezuela, Colombia, Ecuador, Peru, and Brazil.
Threats: The animal does fall prey to subsistence hunting at times, but the fact that it is usually found at considerable height in the canopy means it is largely safe from human activities.
If the conservation status of sloths is a matter of concern, it's for a reason. Of the five sloth families to have ever existed on the planet, three have been completely wiped off. These sloth species thrived on the planet about 10,000 years ago. Their extinction was most probably triggered by climate change at the end of the last Ice Age and human activities. It can be no coincidence that species that thrived on both continents for years together, disappeared all of sudden when humans entered the picture. That all the extant species of sloth are threatened by habitat destruction resulting from human activities might be an indication that the history is repeating itself.
PS: If you ever visit Costa Rica, you should make it a point to visit the Sloth Sanctuary. The one-of-its-kind sanctuary is by far your best bet if you are to see different types of sloths. Also, the people involved are doing a commendable job for the conservation of this animal.
