In addition to the fishing restrictions announced earlier this week on the Lower Madison and Upper Big Hole Rivers, Montana Fish, Wildlife and Parks will also be imposing the following fishing closures from 2 p.m. to midnight daily beginning Thursday, July 25 until conditions improve:
- Jefferson River – entire river
- Big Hole River – Notch Bottom Fishing Access Site (southeast of Glen) to the mouth
Water temperatures in Jefferson and in the noted portion of the Big Hole have exceeded 73 degrees for a week. Flows have also dropped, reaching the triggers identified for fishing restrictions in respective watershed drought management plans.
FWP’s drought policy calls for angling restrictions to be imposed when maximum daily water temperatures equal or exceed 73 degrees for three consecutive days. The preferred water temperature for rainbow and brown trout is about 55-57 degrees. Brown trout, rainbow trout and mountain whitefish caught when water temperatures exceed 73 degrees exhibit an increased mortality rate (4% to 28%) due to the cumulative stress.
Biologists will continue to monitor the conditions on all southwest Montana rivers.
For details on all emergency angling restrictions and other drought updates, go to the FWP home page at fwp.mt.gov and select Drought & Fire under the Hot Topics heading, or check the FWP online fishing guide.
Montana Fish, Wildlife & Parks