With the Boulder River near Big Timber between Bozeman and Billings returning to its normal low-and-clear status, the fishing is back to best being done walking-and-wading. The heavy rains of last weekend caused the river to bump some, but is now flowing around 200 CFS. This is a great level for walk and wade fishing, but the fishing isn't particularly easy right now. For good anglers and strong waders, the Boulder River is a good alternate option to some of the more well known rivers in the southwest Montana. The Boulder River is low and gin clear right now, with flows holding steady, though they will continue slowly dropping. This is a near-impossible level for floating anything larger than a one person pontoon or kayak.
Don't expect things to get going until late morning or mid-day as the water in the Boulder River is running low, clear, and cold this time of year. Heavy frosts are the norm on the Boulder and the trout follow suit by not starting their daily feeding window till at least 10 AM or even as late as Noon or 1 PM.
Best Flies for the Boulder
20 incher #6-10
Duracell #14-18
Prince #12-16
Blowtorch #14-18
Lil' Spanker #12-18
Chubby Chernobyl (Purple, Yellow, Tan) #6-14
Stimulator #8-16
Foam Run Caddis #12-16
Baby Gonga (Olive) #4-8
Mini Dungeon (Olive, Natural, Tan) #4-8
The Month Ahead:
The Boulder sees a few browns that make their way up from the Yellowstone River in the fall. This is a cold mountain river and as we get later into the fall the water temps drop quickly and fishing is best in the afternoons.
Long Term Fishing Forecast:
By the end of October the Boulder gets pretty cold. It can still produce but there will be better late fall options in the area as the big browns running out of reservoirs take top billing.
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