Since then, the couple opened an anglers shop, guide service, purchased a lodge, and raised their son. They take pride in showing tourists the best spots to catch and release prized rainbow trout beneath craggy cliffs carved by the Colorado River.

But it could all soon change as warmer water temperatures threaten fish survival and the Gunn’s livelihood.

Key Colorado River reservoirs Lake Powell and Lake Mead are both only about one-quarter full. The continued drop, due to overuse and an increasingly arid climate, is threatening the fish and the economies built around them.