Sloths: Slow to Move, Quick to Learn

At the National Aquarium, the Linne's two-toed sloths in our Upland Tropical Rain Forest habitat have learned a husbandry behavior known as target training. Our team uses operant conditioning, a process that provides paired associations with behaviors. Using positive reinforcement, the animals are rewarded for completing a specific action.

In the case of the sloths, they've learned to touch their nose to a buoy that is held by an Aquarium staff member. Once they complete this action, the behavior is marked by a clicking noise—just like you might use to train your dog at home—which signifies that the action was completed correctly. They're then positively reinforced with a treat, although the type of reward differs depending on the sloth. Grapes are the snack of choice for 15-year-old female Ivy, while 24-year-old Westley is a big fan of zucchini and squash.

So, why target train the sloths? There are several reasons. First—despite their soft, huggable appearance—sloths can't be easily picked up and moved, so target training allows our rain forest staff to "walk" the sloths around the perimeter of the exhibit. It also allows our team to lead the sloths to an off-exhibit area if they need individual attention, such as medical exam or a nail trimming session.

Another benefit of target training for sloths—and all other animals that are target trained at the Aquarium—is that using this type of positive reinforcement helps to instill a bond between the animals and our staff.

Although target training is a common practice at many aquariums for all types of animals, it's a pretty unique strategy for training sloths in human care. It turns out that there's more to being a sloth than snoozing in the treetops—at least at the National Aquarium!