"Many parts of the U.S. have been getting warmer over the past several decades, and also experiencing persistent drought. Wildlife often can't adjust. Among the species that are struggling is one of the American West's most highly prized fish — the cutthroat trout.
In springtime, you can find young cutthroats in the tiny streams of Montana's Shields Basin. Bend over and look closely and you might see a 2-inch fish wriggling out from under a submerged rock — the spawn of native cutthroats.
The cutthroat is picky about where it spawns; the fish seeks cold mountain streams with just the right amount of water from spring snowmelt."