WASHINGTON— The U.S. Fish and Wildlife Service today proposed protecting the pygmy three-toed sloth under the Endangered Species Act. The proposal responds to a 2013 petition filed after officials from a Texas aquarium unsuccessfully attempted to import six of the creatures from an island off Panama.

The pygmy sloth — the world’s smallest sloth — is considered critically endangered by the International Union for Conservation of Nature. A 2017 study showed only 48 individuals left in the wild, and there are likely fewer alive now. The sloths face destruction of their forest habitat, opportunistic hunting, increased genetic inbreeding, trade and a lack of meaningful protections under Panama law.

“It’s great news that the U.S. government is finally taking action to protect the adorable but extremely endangered pygmy sloth,” said Tara Zuardo, a senior advocate at the Center for Biological Diversity. “With so few pygmy sloths left in the wild, it’s crucial they’re granted every protection under the law as soon as possible.”

First identified as a distinct sloth species in 2001, pygmy three-toed sloths live on Isla Escudo de Veraguas in Panama. The species does not fare well in captivity, making captive breeding efforts a challenge.

The Dallas World Aquarium officials attempting to capture the sloths in 2013 were confronted by protestors and police, who barred them from leaving the airport. The animals were then returned to the island.

If the pygmy sloth is listed as endangered under the Endangered Species Act, commercial trade would be banned and any trade for zoological purposes would be strictly regulated. Trade in pygmy sloths is currently regulated by the Convention on International Trade in Endangered Species.