Montana Fish, Wildlife and Parks (FWP) imposed “hoot-owl” fishing restrictions on the Bitterroot River drainage starting August 1, 2026, citing continuously rising air and water temperatures across western Montana.
The restrictions prohibit fishing from 2 p.m. To midnight each day. FWP designed the rule to cut fish mortality during peak heat hours, when warm water holds less dissolved oxygen and trout stressed by angling are far less likely to survive release.
Two Bitterroot Tributaries Now Restricted Under the New Order
The West Fork Bitterroot River is now restricted from Painted Rocks Dam to its confluence with the East Fork. The Upper East Fork Bitterroot River is restricted from Star Falls to the Highway 93 crossing at Sula. The section of the East Fork below Sula, running to its confluence with the West Fork, was already under hoot-owl restrictions before August 1.
FWP has also placed restrictions on other sections of major rivers across southwest Montana. The agency maintains an updated map of all active closures on its website.
Hoot-owl restrictions are a standard FWP temperature-response tool for coldwater fisheries. Trout species begin experiencing physiological stress when water temperatures climb above roughly 67 degrees Fahrenheit, and recovery from angling becomes increasingly unlikely as temperatures rise further. The afternoon and evening restriction targets the window when water is hottest and fish are most vulnerable.
Montana’s rivers have faced recurring heat events and drought conditions in recent summers. Restrictions like these are temporary but can remain in place for weeks depending on whether temperatures drop.
What You Can Do Now
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Check FWP’s current restrictions map before fishing. Visit fwp.mt.gov for a live map of all active closures. Hoot-owl boundaries can expand as temperatures rise. Violating restrictions can result in a citation and fine.
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Call Montana Governor Greg Gianforte’s office at (406) 444-3111 and ask his administration to strengthen stream flow protections and water quality standards that reduce chronic heat stress on Montana’s coldwater fisheries during drought years.
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Contact your Montana state legislators at leg.mt.gov and ask them to support funding for FWP stream temperature monitoring and instream flow programs. Restoration funding helps rivers recover between heat events.
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Report violations or temperature concerns to FWP’s wildlife tip line at (800) 847-4687 (TIP-MONT). The hotline operates around the clock.
Sources
Daily Montanan: FWP Adds Fishing Restrictions to Bitterroot River Montana FWP: Current Fishing Restrictions and Closures Map Montana FWP: Hoot-Owl Fishing Restrictions Explained KFF Health News: Extreme Heat and Freshwater Ecosystems Under Climate Pressure