Colorado Parks and Wildlife has asked anglers to stay off several streams this summer, following a trend amid historic drought.
Late last month, officials ordered voluntary closures across several waterways in the state's parched southwest, including parts of the Animas, San Juan and Dolores rivers. The request was to stay away after noon, when temperatures have reached levels harmful to cold-blooded trout.
A CPW news release at the time reported consistent measurements above 71 degrees in those streams, with flows below 50% of average. The release indicated "especially hard" conditions on the Dolores River below McPhee Reservoir, where levels have hovered around 33% of normal.
Temperatures rise when water levels decrease; fish are thought to be strained when water temperatures creep above 67 degrees.
“I liken it to how nobody wants to be exercising outdoors when it’s over 100 degrees outside,” aquatic biologist Jim White said in the release. “That’s kind of the same thing we’re imposing on these fish when folks are fishing when the water temperatures are that hot. When you’re yanking them out, it’s hot and stressful. Alleviating that stress on the fish population is good practice.”
The summer also has seen voluntary closures along the Colorado and Eagle rivers. Since June, close to 20 river segments in total around the state have been subject to closure.
For guides and outfitters, the closures have served as a warning for the future, said Scott Willoughby, the Eagle-based representative for Trout Unlimited.
"You're seeing outfitters that are forced to start their days earlier and end them earlier," he said in a previous Gazette interview.
As the climate changes, experts have said anglers will have to adapt along with the trout that seek cooler waters in higher elevations. That's happening, Willoughby said.
"Flexibility really becomes adaptability," he said. "Which is something we've always done, but it's become more of a mandatory consideration. And frankly, we're running out of water faster, so everything is shrinking."