BILLINGS, Mont. (AP) — Federal officials will review whether enough is being done to protect grizzly bears in the contiguous U.S. states after environmentalists sued the government to try to restore the fearsome animals to more areas, according to a court settlement approved Monday.

The review must be completed by March 31, 2021, U.S. District Judge Dana Christensen ordered.

Grizzly bears have been protected as a threatened species in the U.S. — except in Alaska — since 1975, allowing a slow recovery in a handful of areas. An estimated 1,900 of the animals live in portions of Wyoming, Montana, Idaho and Washington state.

Tens of thousands of grizzlies once populated western North America before hunting, trapping and habitat loss wiped out most by the early 1900s.

Federal wildlife officials said in 2011 that additional areas should be considered for grizzly bear recovery, but that work has never been completed.

In a lawsuit filed in June, the Center for Biological Diversity sought to force officials to consider restoring grizzlies to parts of California, Colorado, New Mexico, Arizona, Utah, Nevada and Oregon.

“There are a lot of places where grizzly bears used to live where we believe they could currently live,” said Andrea Santarsiere, an attorney for the group.

The U.S. Fish and Wildlife Service agreed to the grizzly status review that could lay the groundwork for new restoration plans, though that’s not guaranteed. Agency officials did not immediately respond to telephone and email requests seeking comment.

One area previously mentioned by federal officials as having potential for grizzlies is southwestern Colorado’s San Juan mountain range.

Advocates of returning bears and other predators to the state have grown more vocal in recent years. They are now trying to get an initiative on the 2020 ballot to have the state reintroduce gray wolves west of the Continental Divide. Ranchers, hunters and other interests are campaigning against the proposal.

A review of the states in the continental U.S. would look at potential habitat for grizzlies, people who live in those areas and how far they are from existing grizzly populations, said Chris Servheen, former coordinator of the government’s grizzly bear recovery program.