Bigmouth Buffalo
The Bigmouth Buffalo (Ictiobus cyprinellus) is Montana's largest member of the sucker family and one of North America's most remarkable freshwater fish.
These barrel-shaped fish are native to Montana, primarily inhabiting the Missouri River drainage including the Milk River system.
Scientific Name: Ictiobus cyprinellus
These extraordinary fish can live over 112 years and reach lengths exceeding 4 feet and weights over 70 pounds, making them true freshwater giants. These barrel-shaped fish are Montana's largest member of the sucker family.
Fishing in Montana
Missouri River
Sun River
Smith River
Belt Creek
Marias River
Benton Lake
Holter Lake
Teton River
Dearborn River
Little Muddy Creek
What to know
Habitat Distribution
These barrel-shaped fish are native to Montana, primarily inhabiting the Missouri River drainage including the Milk River system.Key Locations
In Montana, they're found in large rivers and reservoirs, particularly the lower Missouri River and Yellowstone River systems, with the downstream portions of the Yellowstone River serving as important rearing areas. Target large rivers like the Missouri and Yellowstone.Specific Spots
Focus on slower-moving sections, backwater areas, pools, and current edges where buffalo congregate. Look for fish near drop-offs, outside bends of rivers, dams and falls where current creates feeding opportunities, and areas with overhanging vegetation or riparian zones. Adults commonly school together in deeper pools and runs.Bigmouth Buffalo FAQ
Answers from onWater's species guide.
What are the best lures and bait for Bigmouth Buffalo in Montana?
Use bread or dough balls, small minnows, and cut bait - all should be heavily scented.
What flies work for Bigmouth Buffalo in Montana?
Small flies are most effective, particularly nymph patterns that imitate their planktonic prey. Midge patterns in sizes 14-20 work well, along with small streamers with olive, brown, and white coloration.
When is the best time to fish for Bigmouth Buffalo in Montana?
The best fishing occurs during late spring through early fall, with peak opportunities from June through September when water temperatures are warmest and fish are most active.
How do you catch Bigmouth Buffalo in Montana?
Drift fishing and still fishing are the most productive techniques, often fishing near the bottom where plankton concentrates. Fly fishing requires delicate presentations with small nymphs dead-drifted under indicators, similar to trout fishing but targeting areas where you observe buffalo feeding or mudding.
What do Bigmouth Buffalo eat?
Bigmouth Buffalo are unique among suckers as filter-feeders with terminal mouths, using fine gill rakers to strain plankton from the water. Their diet consists primarily of zooplankton including cladocerans and copepods, supplemented by diptera larvae, crustaceans, and algae.
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