ANCHORAGE, Alaska— The Center for Biological Diversity filed an appeal with the U.S. Court of Appeals for the 9th Circuit today challenging the Trump administration’s denial of Endangered Species Act protection to Pacific walruses. The Center’s lawsuit says officials have ignored the threat that climate change and the loss of Arctic sea ice poses to the walrus’ survival.

Walruses perform all their essential life functions on Arctic sea ice, which has dropped to record low coverage and is expected to continue its decline as the Arctic heats up at twice the background global warming rate. The U.S. Fish and Wildlife Service found in 2011 that the walrus warranted protection because of climate change, but the Trump administration reversed course and found the species no longer merits protection. In September the District Court in Alaska upheld the Fish and Wildlife Service’s finding.

“Pacific walruses could be headed for extinction if the courts don’t force the Trump administration to help them,” said Emily Jeffers, an attorney at the Center. “The Arctic sea-ice habitat walruses rely on is disappearing at a record rate. They deserved protection back in 2011, and the case for giving them federal protection is even stronger today. These majestic creatures desperately need our help.”

The species’ need for protection has only grown more urgent since 2011 as Arctic sea-ice extent continues to hit numerous record lows. Recent reports show Chukchi Sea ice forming later than ever this year, disrupting the walruses’ main foraging grounds. Models representing the international scientific consensus on climate change point to a dramatic loss of the animals’ sea-ice habitat through at least the end of the century.

Pacific walruses, known for their massive size and ever-growing pair of tusks, need sea ice for courtship, giving birth, nursing their young, and resting during foraging and molting. Without strong action to reduce carbon pollution, scientists project summer sea ice will disappear in the next decade or two.