The main predators of sloths are jaguars, large birds of prey and snakes. The sloth's long claws, which are more often used for climbing trees and hanging from branches, are its only defense against predators in the wild. Sloths are most vulnerable during their infrequent trips down from the trees to ground level.
The slow-moving sloth is no match for the jaguar, which is the third-largest cat in the world. Known for its power and agility, the jaguar can ambush and kill a sloth with one bite. While it does most of its hunting on the ground, the jaguar can even follow a sloth up into the trees.
Large birds of prey, specifically the harpy eagle, also hunt sloths. The harpy eagle is the largest and most powerful raptor found in the Americas. Researchers in Brazil collected the remains from prey offered to the harpy's nestlings and determined that 79 percent of the harpy's prey was composed of two sloth species. Bradypus variegatus amounted to 39 percent of the harpy's prey, and Choloepus didactylus totaled 40 percent. However, the majority of sloth deaths in Costa Rica do not occur because its natural predators kill them. Instead, they are due to contact with electrical lines and human poachers.