Portions of the Dearborn, Sun and Smith rivers will be closed to fishing from 2 p.m. to midnight beginning Friday to protect trout as warm weather has raised the water temperature.
The "hoot-owl" closures enacted by Montana Fish, Wildlife and Parks will be enforced on the Dearborn from the Highway 435 bridge to the confluence of the Missouri River; on the Smith from the confluence of the North and South forks to Eden Bridge; and on the Sun from the Highway 287 bridge to the mouth of Muddy Creek.
FWP's drought policy provides for angling closures when flows drop below critical levels for fish, when water quality is diminished, or when maximum daily water temperatures reach at least 73 degrees for three consecutive days.
The preferred water temperature for rainbow and brown trout is about 55-57 degrees. Temperatures of 77 degrees or more can be lethal to trout.
"All three rivers have experienced high water temperatures between 74 and 77 degrees since early July” said Grant Grisak, Region 4 fisheries manager in Great Falls.