Trout: Rising Water Temps & Closures

Grab a thermometer and be ready to use it the next time you go fish any Colorado river this summer.  Water temperatures can clue you into what the fish and their food are doing, but more importantly this season, temps are rising all over the state early, river flows are decreasing in most drainages, and these factors combined with other elements are leading to fishing closures.  Help us keep tabs on the river temps - next time you are out, submit a river water temp reading. And for lakes too!

Closures are implemented because of greater potential for angler-related fish mortality rates.  Higher water temps decrease dissolved oxygen, and a fighting trout will need more of what there is less of to survive.

Some of the CPW closures are voluntary, meaning they are suggested so you know to be alert, and you likely won't get a fine. Here are some guidelines in deciding whether or not to fish a river whether or not there are voluntary closures implemented...

The chart from Colorado Trout Unlimited below explains suggestions.  Paraphrased:

Below 65 degrees F: Trout are hungry and happy, go fish!

65-68 degrees F: Trout slowing down, fish heavier tippet, decrease length of fight, keep trout in water, skip out-of-water photos, be patient with revival.

Above 68 degrees F: Trout stressed, need break, stop fishing for them.

Note that one of the CPW's determining factors in enacting closures is that the max daily water temps reach above 71 degrees F.

Other articles to check out for more information for you to make informed decisions:

CPW fishing closures are enacted to protect the fishery.  If you are planning to release trout, abide by these rules.  If you plan to keep trout, well then, I suppose this doesn't necessarily apply, except that if you catch one you don't want to keep and you release it, it's more likely to perish. Know the closure may be enacted partially because low flows force fish to congregate in smaller areas versus spreading out throughout the river, and this compression of fish makes locating them easier, compounding the negative impact on the overall fishery.

Something I found interesting is that two of the four factors in CPW's determination of making a closure voluntary are: 1) anglers are likely to follow voluntary closure, and 2) education is likely to reduce angling related mortality.  This is from the decision-making tree linked below. So this takes a bit of teamwork here, please work to understand all this and educate others.  

Current Closures as of today 7-19-21 (generated from this page on the CPW website.  Check the CPW fishing conditions page for more current updates.)

Mandatory - Full day: Yampa River (0.6 mile downstream of Stagecoach Reservoir dam within the boundary of Stagecoach Reservoir State Park) Date Implemented: 24-May-21

Voluntary - After 12:00 pm: Dolores River (From McPhee Reservoir dam downstream approximately 12 miles to Bradfield bridge (CR S) ) Date Implemented: June 24,2021

Voluntary - After 12:00 pm: Tomichi Creek (4 miles of Tomichi Creek on the Tomichi Creek SWA east of Gunnison) Date Implemented: 7-Jul-21

Voluntary - Full day: Colorado River (From the Hwy. 9 bridge at Kremmling downstream to the Hwy.13 bridge in Rifle) Date Implemented: 7-Jul-21 (note: July 12, REMOVED only for the Hwy. 9 bridge at Kremmling downstream to State Bridge section.  As of July 12th, the voluntary, full day fishing closure REMAINS in effect from State Bridge downstream to the Hwy.13 bridge in Rifle.)

Voluntary - Full day: Colorado River (From State Bridge downstream to the Hwy.13 bridge in Rifle) Date Implemented: 7-Jul-21 (note: July 20, MODIFIED to a 12:00pm voluntary fishing closure only for the State Bridge to Red Dirt Creek confluence  (downstream of Burns) section.  As of July 20th, the voluntary, full day fishing closure REMAINS in effect from the Red Dirt Creek confluence downstream to the Hwy.13 bridge in Rifle.)

Voluntary - Full day: Yampa River (From the Chuck Lewis State Wildlife Area to the western edge) Date Implemented: 8-Jul-21

Voluntary - After 12:00 pm: Yampa River (Within the boundaries of Yampa River State Park, just west of Hayden) Date Implemented: 13-Jul-21

Voluntary - After 12:00 pm: Yampa River (Within the boundaries of Yampa River State Wildlife Area, between Hayden and Craig) Date Implemented: 13-Jul-21

Voluntary - After 12:00 pm: Elk River (Within the boundaries of Christina State Wildlife Area) Date Implemented: 13-Jul-21

Here is a decision tree chart explaining how CPW decides to implement a fishing closure: https://cpw.state.co.us/Documents/Fishing/Fishing_Closure_Decision_Tree.pdf

So when the water gets too warm, fish at night, fish early in the day, or don't fish trout at all.  Pay attention to the water temps of the river throughout the day and call it quits when it is too warm and the fish are struggling.

Now is a great time to get into carp fly fishing!

Check out a great podcast I just listened to about night trout fishing.  It is the Wet Fly Swing podcast hosted by Dave Stewart.  The episode is called "Night Fishing for Trout with Phil Croff", episode 230.  I'm going to do more of this given the daytime crowds and water temps!