The gray wolf population has recovered to the point that it can be safely removed from the federal list of threatened and endangered species, the U.S. Fish and Wildlife Service said Friday in a proposal that environmental groups suggest is premature.

Under its proposed delisting plan, the wildlife service would return management of gray wolves to the states where they dwell. Federal protections for wolves have been in place since 1978.

In a second proposal, the service would maintain protections and expand recovery efforts for the Mexican gray wolf in the Southwest, where it remains endangered.