As Water Temperatures Cool, FWP Lifts Fishing Restrictions on North Fork Flathead River

Less than two weeks after Montana Fish, Wildlife and Parks (FWP) took the unprecedented step of restricting angling on the North Fork Flathead River amid record-breaking temperatures, the agency’s fisheries biologists have determined that water temperatures have cooled sufficiently to justify lifting the restriction, effective Wednesday, Aug. 7.

“Air temperatures are moderating and updated weather forecasts call for cooler nights and wetter conditions, especially higher in the drainage. Water temperatures have met the criteria to lift fishing restrictions on the North Fork and FWP expects the temperatures to remain cool,” according to an Aug. 6 press release from FWP’s Region 1 headquarters.

FWP biologists had been closely monitoring the water temperatures of local rivers and streams amid a summer heat wave in northwest Montana, where water temperatures in the North Fork started bumping up against daily records in early July. FWP implemented hoot-owl fishing restrictions on the North Fork on July 24, prohibiting fishing from 2 p.m. to midnight each day to protect fish that become more susceptible to disease and mortality when conditions, such as low flows and high water temperatures, combine with other stressors — including catch-and-release fishing.

FWP’s Statewide Fisheries Management Plan identifies temperature criteria for westslope cutthroat trout, triggering restrictions when water temperatures reach or exceed 66 degrees Fahrenheit for three consecutive days. The criteria for bull trout on the South Fork Flathead River, which is the only river in which FWP manages a catch-and-release fishery for bull trout, is 60 degrees, also for three consecutive days.

Similar to last summer, the entire Flathead River basin is experiencing low flows and increasing water temperatures due to below-average winter snowpack, early runoff and hot, dry summer conditions. Flows in the North, South, and Middle forks of the Flathead River were below average for this time of year, while water temperatures had consistently been hitting stressful levels for trout, particularly native species like westslope cutthroat and bull trout.

Even with the restrictions lifted, anglers can help reduce stress for fish like westslope cutthroat trout by following these practices when catching and releasing fish:

• Remember: Only single-pointed hooks are allowed in the Flathead drainage upstream of Teakettle Fishing Access Site on the mainstem Flathead River, and on the Swan River from Piper Creek Bridge downstream to Swan Lake. Treble hooks and double hooks are prohibited in these stretches.

Fish during the coolest times of day, where permitted. 

• Land the fish quickly. 
• Wet your hands before handling the fish.  
• Keep the fish in water as much as possible.  
• Remove the hook gently. Using artificial lures with single and barbless hooks can make hook removal faster and easier.  
• Let the fish recover before releasing it.
• Consider fishing areas with less stressful temperatures and conditions, such as larger lakes or reservoirs, or higher elevation waterbodies.

For more information and updates, visit https://fwp.mt.gov/news/current-closures-restrictions/waterbody-closures or contact the FWP Region 1 office at 406-752-5501.