Here’s the release from Colorado Parks and Wildlife (Michael Seraphin):
The heat wave sweeping Colorado has created a situation where river temperatures on the Upper Arkansas will be regularly monitored for impacts to trout. At the present time, Colorado Parks and Wildlife is taking a position of “cautious optimism.”
The reduction is snowpack last winter means less icy-cold water in the river during what is usually a time of heavy water. The result has produced plenty of insects for forage and provided trout with better opportunities to feed, which means fish are growing well and are in good shape. The flip side is that water that gets too warm can start to stress the fish.
“We are monitoring water temperatures at a number of locations along the river from Salida to Parkdale on a regular basis so we will be able to advise anglers on the best course of action,” said Rob White, park manager of the Arkansas Headwaters Recreation Area.
White added that water has been set aside this year to provide adequate flows for whitewater boating and to protect the fishery through July and August.
According to aquatic biologist Greg Policky, his concern from a fishery standpoint is that the water temps are increasing. So far, water temperatures have not reached the same point as 2002. “In that year, we saw water temperatures at Parkdale rise to nearly 80 degrees,” said Policky.
Since mid-June, temperatures on the Arkansas have been moderate, with a 72-degree reading at Lone Pine on June 26.
Anglers on the Arkansas are encouraged to continue fishing, but asked to be careful with the release of their catch. Over-playing fish, and less than delicate release of fish, could be lead to injury – particularly as water temperatures warm.
The amount of rain and the air temperatures in July and August will determine how warm the water may get.
“If there is fish mortality, it happens for a variety of reasons, so seeing a few dead fish on the side of the river is not cause for alarm yet,” said Policky. He added that there are about 4,000 to 4,500 fish for every mile of river, so what anglers do not see is the huge number of live fish beneath the surface.
Colorado Parks and Wildlife has issued fishing advisories and asked for voluntary compliance with fishing restrictions on the Yampa and the White Rivers in western Colorado and is considering other requests for voluntary restrictions in other parts of the state, but no restrictions are currently being considered for the Upper Arkansas. If daily monitoring shows the need for restrictions, public notification will occur.