1. Fitness costs of reproduction are expected when resources are limited. Costs drive the evolution of life-history strategies and can affect population dynamics if females change their allocation of ...

Mountain Studies Institute’s project supports work of public land and wildlife agencies In Southwest Colorado, a growing army of everyday scientists scours the mountains for Rocky Mountain bighorn ...

The Pikeview Quarry, barely outside of the cul-de-sacs and two-car garages of the Mountain Shadows subdivision, seemed like an odd place to find one of Colorado’s most intrepid species. Bulldozers, ...

Overhead, desert bighorn sheep cross U.S. Highway 93. The sheep aren’t headed to Las Vegas, like other travelers on the highway near Hoover Dam on the Arizona-Nevada border. The bighorn are using ...

Kim Keating / USGS Bighorn sheep and domestic sheep love to hang out and get nose-to-nose with each other. That’s a problem. Domestic sheep can carry a pathogen that’s highly contagious, and often ...