Federal officials are moving too slowly to protect the hippo from a wildlife trade that sends more hippo body parts to the United States than any other country in the world, a collaborative of animal conservation organizations said this week in announcing plans to sue the U.S. Fish and Wildlife Service.

"While the U.S. government is dragging its feet, hippos are disappearing from the wild," stated the coalition of groups that includes the Humane Society of the United States, Humane Society International and the Center for Biological Diversity.

The wildlife service announced a year ago that a petition from the animal groups contained "substantial" information to show listing might be needed to protect hippos from poaching and trade in its body parts, but the agency missed its 12-month deadline to decide whether to protect hippos under the Endangered Species Act.

“Federal protections are critical for species like hippos who are being pushed to the brink of extinction,” said Tracie Letterman, vice president of the Humane Society Legislative Fund.

With the U.S. the leading importer of hippo parts and products, the federal government "must lead by example and list hippos under the Endangered Species Act," Letterman said.

As few as 115,000 adult hippos may remain in the wild, the coalition of wildlife groups said Thursday.

The International Union for Conservation of Nature lists the "common hippo," one of two hippo species in Africa, as "vulnerable," estimating its population at 125,000-148,000, but declining. Reports indicate the population is half what it was historically. Wild hippos were historically found across Africa in more than three dozen countries, but are no longer found in Algeria, Egypt, Liberia and Mauritania, the wildlife service said.

Because hippos aren't on the federal protected species list, trade in its body parts – including teeth, skulls, ivory, skin and meat – continues unfettered, the wildlife groups said. The groups said at least 3,081 hippos were killed between 2009-2018 to fuel the trade legal in the U.S.

Endangered Species Act50 years ago, Democrats and Republicans acted together to protect species

The species continues to face "myriad threats that are exacerbated by international trade in their parts," said Adam Peyman, wildlife programs director for Humane Society International.

The Humane Society groups reported their undercover investigation in 2022 found thousands of hippo items for sale in this country, including belts, shoes, purses, and carving on knives and bottle openers.

“Hippos play a crucial role in the aquatic ecosystems where they live but the United States has an appetite for frivolous hippo products," said Tanya Sanerib, international legal director at the Center for Biological Diversity. "It's time for federal officials to stop yawning at deadlines and take the next step toward protecting the species from US demand.”

Other countries also have declined to increase protections for hippos. A proposal to upgrade the status of hippo protections on the IUCN's red list failed during an international meeting on trade in October 2022, with the European Union using all of its 27 votes against the measure,

The wildlife service stated in its initial review that the additional protections might be needed because of loss and degradation of the hippo's habitat, climate change, need for water and war. The agency has since received 110,571 public comments, many in a form letter version, regarding the potential listing.