SOCORRO COUNTY, N.M. (KRQE) – When you hear their call, you know it's fall. The Sandhill cranes have made their way to New Mexico. Sandhill cranes are synonymous with the changing of seasons in New Mexico. At Bosque del Apache, the best time to see the cranes is during sunrise or sunset because during the day they're foraging for food. Otter population making comeback in New Mexico A wildlife expert said an abundance of sandhill cranes indicates a healthy environment. "Sandhill cranes are important to New Mexico for many reasons. They provide a lot of wildlife viewing opportunities. We see in New Mexico or in the middle Rio Grande Valley, about 80% of the rocky mountain population of Sandhill cranes overwinters here and that's up to 20,000 cranes," said U.S. Fish and Wildlife Service biologist Shayla March. Bosque del Apache National Wildlife Refuge's annual Sandhill Crane Festival kicks off on December 12.