ANCHORAGE — A seal that depends on Arctic sea ice for reproduction will receive threatened species protection, the 9th U.S. Circuit Court of Appeals ruled Monday.

A three-judge panel overturned a lower court decision and ruled that the National Marine Fisheries Service acted properly in listing ringed seals as a threatened species because of projected loss of sea ice due to climate warming.

The decision reverses a ruling by U.S. District Court Judge Ralph Beistline of Anchorage, who in March 2016 said the agency’s decision was speculative.

The decision is closely related to a judgment on another ice-dependent species, bearded seals. Beistline, the judges said, required long-range data demonstrating the decline of ringed seals, information that is not available and is not required under the Endangered Species Act for a listing.

“The district court cannot require the agency to ‘wait until it has quantitative data reflecting the species decline, its population tipping point, and the exact year in which that tipping point would occur before it could adopt conservation policies to prevent that species’ decline,’” the judges wrote.

The agency determination that ringed seals are likely to become endangered was reasonable and based on the best science available as the law requires, the judges said.

Ringed seals get their name from small light-colored circles on their coats. The smallest of Alaska’s ice seals, ringed seals are the only ones that thrive in completely ice-covered Arctic waters. They use stout claws to dig and maintain breathing holes.

When snow covers those holes, females excavate snow caves, where they give birth to pups that cannot survive in ice-cold water. Pups are susceptible to freezing until they grow a blubber layer.

Ringed seals are the main prey of polar bears, which often catch breeding females or pups by collapsing lairs.

Early breakup of sea ice, less snow and even rain threatens lairs, exposing pups to polar bears, Arctic foxes and freezing temperatures.

The National Marine Fisheries Service concluded that the ringed seal likely would be endangered based on climate change models from the Intergovernmental Panel on Climate Change projecting continued loss of sea ice and higher temperatures through the end of the century.

Kristen Monsell, an attorney for the Center for Biological Diversity, which filed the listing petition in 2008, said Beistline wanted very specific information about ringed seal population decline. The law does not require that degree of specificity, Monsell said.

“Particularly here, waiting for perfect science would essentially condemn the species to extinction because it would simply be too late at that point to save them because their sea ice habitat would already be gone,” she said.