Big Hole River

The Big Hole runs 153 miles from its headwaters in the Beaverhead Mountains at Skinner Lake through the wide Big Hole Valley to its confluence with the Beaverhead at Twin Bridges, where the two combine to form the Jefferson. The river is one of Montana's classic freestones — undammed, meandering through wide valley floors and rocky canyon sections, with widely varying character along its length. Wild rainbows and browns make up most of the trout fishery, but the Big Hole is famous as the only remaining home of fluvial (river-dwelling) Arctic grayling in the lower 48 — a population restricted to about 20 miles of upper river between Wisdom and Wise River. Whitefish and an occasional brook trout round out the fish list. Average size is 12-16 inches with regular fish over 18 in the lower river.

Timing on the Big Hole is unusual — the river runs cold and big through the salmon fly hatch in late June and stays cold into July, then warms quickly in August. Hoot owl restrictions are common in July and August on the middle and lower river. The salmon fly hatch typically starts at Glen around June 20 and works upstream to Wise River over about 10 days. Golden stoneflies overlap and run through July. The yellow sally hatch is genuinely heavy on the Big Hole — sizes 14-16 in late June through July. Caddis are present but secondary to the stoneflies and mayflies. PMDs in July, BWOs in spring and fall. The fall streamer fishing for pre-spawn browns in the canyon below Divide is exceptional. The upper river above Wisdom (in grayling water) closes August 1 to protect spawning grayling and reopens in mid-October.

Wise River is the corridor town for the middle river — Wise River Mercantile and Frontier Anglers are the local fly shops. Twin Bridges is the downstream hub (Twin Bridges Wading Co, Sweetwater Travel). Drive times: 90 minutes from Bozeman, 90 minutes from Missoula via I-15. Public access along the upper and middle river is excellent — Highway 43 parallels the upper river and county roads access the canyon. Below Glen the river runs through more private agricultural ground but FWP fishing access sites bracket the float water. The Big Hole's character changes through its length — wide and slow with low gradient in the Wisdom meadows, faster pocket water through the Maiden Rock Canyon, and wider gravel-bar water from Melrose down to Twin Bridges. Each section fishes differently and rewards local knowledge.