BirdAnalyst
Species · Montana · BBS 2025 Release · 1966–2024

Ruffed Grouse Population Trend in Montana

All statesGeneralists

Ruffed Grouse in Montana has surged: up 153% on the route-weighted index since 1972.

+153%Since 1972TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
38Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
51YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Ruffed Grouse Trends in MontanaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Ruffed Grouse has surged in Montana: up 153% on the route-weighted index since 1972.

Ruffed Grouse Population Forecast in Montana

If the recent trend holds, Ruffed Grouse in Montana is projected to rise about 147% by 2029 — from 0.12 in 2024 to a central estimate of 0.29 (95% range 0.02–0.56). A 5-year backtest shows a typical error of ±90.6%, with 100% of held-out values landing inside the 95% band.

+147%Change by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.29Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.02–0.5695% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±90.6%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Ruffed Grouse in Montana is projected to rise about 147% by 2029 — from 0.12 in 2024 to a central estimate of 0.29 (95% range 0.02–0.56). A 5-year backtest shows a typical error of ±90.6%, with 100% of held-out values landing inside the 95% band.19682029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.280.010.56
20260.290.010.56
20270.290.010.56
20280.290.020.56
20290.290.020.56

Ruffed Grouse Survey Routes in Montana

Routes recording Ruffed Grouse in Montana.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Thompson Riv820211994
Greenoagh 2620102009
Fish Creek620211996
Maynard Coulee420242017
Libby Dam320131979
Greenough320042002
Clinton320211976
Chestnut320221968
Kalispell219941982
Threemile Wa220231999
Polson220152015
Pagil Gulch220242016
St Mary120021972
Victor120231995
Cramer Creek120181996
Elevation Mt120211995
St Regis120211977
Arlee120241977
Augusta120112011
Woodman120231976
Elliston120231980
Inside Road120231999
Sula120071987
Whitefish Lake120192018
East Glacier Park120242015

Ruffed Grouse Population Trend in Other States

alaskaarkansascaliforniaconnecticutgeorgiaidahoindianaiowakentuckymainemarylandmassachusettsmichiganminnesotanevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.