Wildlife advocates and environmentalists say a proposal to lift protections for Yellowstone-area grizzly bears is premature.

The U.S. Fish and Wildlife Service announced Thursday that the large predators have recovered from near-extinction across portions of Wyoming, Montana and Idaho.

The announcement covers an estimated 700 to 1,000 bears in and around Yellowstone National Park.

Sylvia Fallon with the Natural Resources Defense Council says lifting protection would halt the species' recovery and prevent the animals from spreading into new areas.

Other groups also voiced concerns, saying the grizzly population faces emerging threats from the loss of key food sources and the high number of bears killed over conflicts with humans.

Removing protections would allow the states to hold the first trophy grizzly hunts since the 1970s. A decision is due within a year.