To ease pressure on fish trying to endure low and warming water levels, Colorado Parks and Wildlife has enacted a voluntary fishing closure from noon to midnight for the Animas River through Durango, the Dolores River below McPhee Reservoir and the San Juan River through Pagosa Springs.

Temperatures in the rivers have regularly risen above 71 degrees in the past week, and stream flows are below 50% of daily average, according to a CPW news release.

The conditions put extra stress on fish, and anglers may find it difficult to safely release fish that are caught.

The voluntary closure will remain in effect until further notice.

“I liken it to how nobody wants to be exercising outdoors when it’s over 100 degrees outside,” said CPW aquatic biologist Jim White 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.”

White said fish might look fine when they swim off quickly after they’re released, but they expend a lot of energy when caught, and recovery is difficult in low, warm water.

With less water, there is less habitat available for the fish, and warming temperatures mean less oxygen available in the water. That can lead to increased trout mortality.

White said conditions on the lower Dolores River below McPhee Reservoir are especially hard on fish, with water levels an estimated 33% of normal.

Because of water shortages from the drought, fish flows released from McPhee Dam are at 15 cubic feet per second, down from 45 cfs or higher when the water allocated for fish has a full supply. The is the second consecutive year that a fishing closure has been implemented for the lower Dolores.

The Animas River hit 72 degrees at times in the past week and has remained above 65 degrees even late at night, White said.

Fish in the San Juan River through Pagosa Springs also are suffering from low flows and higher temperatures plus receive the additional stress of recreational river tubing.

Many anglers have already started to self-impose the closures.

“We certainly have an educated angling community,” White said. “Most people are willing to refrain from angling in the hot afternoons. It’s a matter of educating some more people and our out-of-town visitors to also help these fisheries out.”

Anglers should fish early to avoid the higher water temperatures commonly seen in the afternoon and seek out high-elevation trout lakes and streams where water temperatures are more suitable.

CPW aquatic biologists will regularly monitor temperatures on the rivers in the coming weeks to let anglers know when conditions have improved.

Anglers should be aware of changing conditions at Colorado’s rivers and streams. For the latest conditions related to mandatory and voluntary fishing closures, go to https://cpw.state.co.us.