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Pygmy Sloths Could Gain Much-Needed Endangered Species Protection

The U.S. Fish and Wildlife Service (FWS) last week announced that the world’s rarest and smallest sloth could deserve protection under the Endangered Species Act (pdf).

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


The U.S. Fish and Wildlife Service (FWS) last week announced that the world's rarest and smallest sloth could deserve protection under the Endangered Species Act (pdf). The Pygmy three-toed sloth (Bradypus pygmaeus) lives only on the tiny Isla Escudo de Veraguas off the coast of Panama and is probably one of the rarest mammals in the world. When I last wrote about the species back in 2012, surveys had only managed to locate 79 of these critically endangered tree-dwellers.

The pygmy sloth's fates have been up and down over the past 18 months. Newer surveys this past April found "a bunch of very healthy babies," according to the Friends of the Pygmy Sloth Facebook page. But seven months before that a U.S. zoo called the Dallas World Aquarium almost set off an international incident by trying to export six sloths from Panama to the U.S., something it had permits from the Panamanian government to do but which set off protests at the airport. The animals, plus two more that were bound for a zoo in Panama, were all returned to Isla Escudo but one of the sloths reportedly died in October following the stressful experience.

In response to this incident, a nonprofit called the Animal Welfare Institute filed an emergency petition with the FWS this past November seeking to add the pygmy sloth to the endangered species list. This protection, if granted, would require any person or organization seeking to import a pygmy sloth into the U.S. to first receive a permit from the FWS, the same process that is required for any other foreign endangered species.


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There's still a long way to go in the process to get the pygmy sloth protected in the U.S. The FWS will now spend the next 12 months officially conducting a status review of the species, which will gather scientific data about the sloth's population, ecology and threats. Once that step is done, FWS will then declare if protection is warranted, which could kick off another 15-month process (at minimum) before any legal protections can be enacted.

FWS also announced that it will follow the same process to determine if two other foreign species, the flat-tailed tortoise (Pyxis planicauda) and spider tortoise (P. arachnoides), also deserve protection under the Endangered Species Act. Both critically endangered species are native to Madagascar and are threatened by habitat loss and the illegal pet trade. Similar to the pygmy sloth, protection of these two species under U.S. law would forbid people or organizations from importing them without the proper permits.

Photo © Sam Kaviar

John R. Platt is the editor of The Revelator. An award-winning environmental journalist, his work has appeared in Scientific American, Audubon, Motherboard, and numerous other magazines and publications. His "Extinction Countdown" column has run continuously since 2004 and has covered news and science related to more than 1,000 endangered species. John lives on the outskirts of Portland, Ore., where he finds himself surrounded by animals and cartoonists.

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