ALBUQUERQUE, N.M. (AP) — A few years ago, ranchers in northern New Mexico were in a contentious dispute with environmental groups and the U.S. Forest Service over access to grazing land in the Jemez Mountains, all because of a tiny mouse.

In 2014, the New Mexico meadow jumping mouse, a rarely seen subspecies in hibernation for most of its short lifespan, was recognized by the U.S. Fish and Wildlife Service as an endangered species requiring habitat protection.

That led to nearly 15,000 acres of riparian areas along rivers and streams in Arizona and Colorado, but mostly in New Mexico — includin...