Fishing closure goes into effect Friday on 18-mile stretch of Big Hole River

Anglers on the Big Hole River near the Powerhouse fishing access site on Aug. 2, 2023. (Photo by Blair Miller, Daily Montanan)

An 18-mile stretch of the lower Big Hole River will be closed to fishing starting Friday because river flows are too low in that area to allow for any safe fishing, Montana Fish, Wildlife and Parks announced Thursday afternoon.

The closure will run from the Tony Schoonen Fishing Access Site, also known as “Notch Bottom,” which is just southeast of Glen, to the Big Hole’s confluence with the Jefferson River near Twin Bridges.

The closure is going in place because river flows in that section fell below 100 cubic feet per second, which triggers the fishing closure in accordance with the state’s drought management plan for the river.

The rest of the river upstream of the Tony Schoonen site remains under hoot-owl restrictions that close fishing between 2 p.m. and midnight each day because of warm water temperatures that can harm or kill trout.

Most of the major cold-water trout rivers in Montana are now under hoot-owl restrictions – from the North Fork Flathead River all the way across the state to parts of the Yellowstone River .

Drought has expanded and worsened in western Montana through July. Beaverhead and Madison counties, where the Big Hole River flows through, are now seeing moderate and severe drought conditions, while further north, several counties are experiencing extreme and exceptional drought.

That is due in part to a very dry July. Dillon, for instance, which is south of the Big Hole, saw 0.32 inches of rain on July 1 and 0.09 inches of rain on July 30, but no other measurable precipitation for the month.

The Helena area saw two days of measurable rain during July for a total of 0.22 inches, according to the National Weather Service. That’s about one-fifth the normal precipitation for July in the area. In Missoula , it rained 0.19 inches on July 30 to bring the monthly total to 0.44 inches, about half the normal amount for July.

FWP and Montana State University researchers have been tagging trout in the basin this year to help understand population sizes and health, and are conducting a fish mortality study, a juvenile fish study, and a fish health study as part of the project to understand why trout numbers have been declining for a decade in the basin.

Initial fish counts earlier this spring on two sections of the Big Hole showed some improvement among brown trout populations and minimal improvement among rainbow trout populations.

Another group that is conducting its own water quality monitoring in the basin, Save Wild Trout, and is submitting that data to the Department of Environmental Quality. But the group also reported algae blooms in the basin and record-breaking water temperatures that were reaching close to 80 degrees Fahrenheit at times.

“Although current river conditions are unfavorable, drought is plaguing much of the state, and wildfires are seemingly sparking every day, Save Wild Trout is making strides towards improving science-based management for our wild trout fisheries to preserve them now and for future generations,” the group said in a newsletter last week recapping the summer so far.