The Colorado River Headwaters Chapter of Trout Unlimited applauds Colorado Parks and Wildlife for taking a stance on high stream temperatures that stress and can kill trout. We are experiencing one of the hottest, driest years in decades and with that we are experiencing stream temperatures that are too hot for the survival of trout.

Trout are a cold water fish because cold water holds more dissolved oxygen which trout require. At stream temperature above 65 degrees F, enough dissolved oxygen can escape into the atmosphere to stress trout. At temperatures of 74 degrees F. trout can die. On the Fraser River the afternoon stream temperatures are reaching 74 degrees F and on tributaries to the Fraser River, afternoon stream temperatures are reaching 72.5. By 1:00 pm stream temperatures have warmed up to 65 degrees F or greater and both Colorado Parks and Wildlife and the Headwaters Chapter of TU recommend that fly fishers quit fishing. Above 65 degrees F trout are stressed. Even a savvy catch and release fly fisher can  easily kill a trout whose oxygen consumption soars when caught.

The Headwaters Chapter of Trout Unlimited is asking all catch and release fishers to fish with a thermometer and stop fishing when stream temperatures reach 65 degrees F. If you don’t own a thermometer, you can purchase one at a local fly shop. Until you can obtain a thermometer you should use the 1:00 pm “Stop Fishing” recommendation from CPW. Based on recent stream temperature trends, our streams are reaching temperatures that stress trout on a daily basis by 1:00 pm. From 1:00 pm through the evening stream temperatures will remain high enough to stress trout. Give the fish a break. Fish streams in the morning and move to lakes in the afternoon.

The long term future of Grand County’s trout fishery depends on how we take care of our trout in drought years like the one that we are experiencing this summer. Treat the trout well and they will be around to enjoy and to create a healthy fishing economy for years to come. To learn more, go the the Headwaters Chapter website at


Kirk Klancke is the President of the Colorado River Headwaters Chapter of Trout Unlimited