State restricts fishing in North Fork Flathead River amid record high temperatures

The Montana Department of Fish, Wildlife and Parks has restricted fishing on the North Fork Flathead River in July amid record high water temperatures.

Beginning July 24, the department prohibited fishing from 2 p.m. through midnight to cause as little stress to fish as possible during the hottest part of the day, according to Dillon Tabish, a Fish, Wildlife and Parks spokesperson.

“When these [water] temperatures are high like they are, 66 degrees, that becomes a stressful temperature for those fish,” Tabish told the Montana Independent. “And then when you have fishing where we have, it’s a catch-and-release fishery, so people are handling fish when they’re catching those trout, and they’re caught and released by anglers, that’s just additional stress. And so that can lead to mortality or fish dying. And so we’re really trying to reduce any additional stressors while those warm water temperatures are present.”

Tabish said the water in the North Fork Flathead River had reached that 66-degree threshold.

So-called hoot owl restrictions — a term that dates back to loggers in the early 20th century who worked in the early morning hours when temperatures were cooler and owls could still be heard — were still in effect as of Aug. 6. The restrictions were in place along the full 153-mile length and both sides of the North Fork Flathead River, from the Canadian border to its meeting point with the Middle Fork Flathead River. Tabish said the restrictions could be lifted later in August, depending on how quickly water temperatures drop.

This is the first time the department has implemented hoot owl restrictions in the Flathead drainage area, according to a July 23 press release.

“FWP biologists have been closely monitoring the water temperatures of local rivers and streams amid a summer heat wave in northwest Montana,” the department said. “Water temperatures in the North Fork have been near or above daily records since early July. Elevated water temperatures negatively impact the health and survival of native westslope cutthroat trout and bull trout.”

The department does commonly institute hoot owl restrictions in other parts of the state each summer, but rarely in northwest Montana, according to the press release.

Climate change has led to an increase in Montana’s average temperature of about two degrees Fahrenheit over the last century, according to the U.S. Environmental Protection Agency.

“I’m not a climate expert, but we’ve had an unseasonably warm, hot summer. We had quite a heat wave in July,” Tabish said. “We had a lower-than-average snowpack up here. And so those are the factors that really lead to these conditions where we’ve got lower streamflows as a result of a lower snowpack and then a hotter-than-average summer.”

Tabish said Fish, Wildlife and Parks came very close to imposing fishing restrictions last year.

“We also had a similarly hotter-than-average July, and our streamflows were even worse last year than they are this year. And so we were pretty close to having to enact hoot owl fishing restrictions last year, but we didn’t end up having to do that,” he said. “Again, I’m not a meteorologist or climatologist, so I can’t speak to that, but it’s certainly been two above-average summers for temperatures up here.”

Biologists with Fish, Wildlife and Parks have said they are concerned about high water temperatures and their impacts on trout in the Middle Fork, South Fork and the main stem of the Flathead River upstream of Evergreen, as well as in the Swan and Thompson rivers. Though the department hasn’t imposed mandatory fishing restrictions in those areas, it has encouraged the public’s help in keeping fish populations safe.

“FWP is not recommending hoot-owl restrictions at this time on these other stretches of water but is encouraging anglers to voluntarily limit their fishing to the morning hours when water is coolest and fish are less stressed,” the department said. “Additional fish stress and mortality can result from human handling when trout are caught and released by anglers.”