BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Ruffed Grouse In Northern Rockies

All regionsNorthern RockiesGeneralists

Ruffed Grouse in Northern Rockies has surged: up 141% on the route-weighted index since 1971.

+141%Since 1971TrendPercent 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 →
101Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Northern Rockies: up 141% on the route-weighted index since 1971.

Forecast

If the recent trend holds, Ruffed Grouse in Northern Rockies is projected to rise about 38% by 2029 — from 0.18 in 2024 to a central estimate of 0.24 (95% range 0.04–0.45). A 5-year backtest shows a typical error of ±54.4%, with 100% of held-out values landing inside the 95% band.

+38%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 →
0.24Projected 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 →
0.04–0.4595% 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 →
±54.4%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 Northern Rockies is projected to rise about 38% by 2029 — from 0.18 in 2024 to a central estimate of 0.24 (95% range 0.04–0.45). A 5-year backtest shows a typical error of ±54.4%, 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 →
20250.240.030.45
20260.240.030.45
20270.240.030.45
20280.240.040.45
20290.240.040.45

Routes In Northern Rockies

Routes recording Ruffed Grouse in Northern Rockies.
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 RivMONTANA82021
Fish CreekMONTANA62021
Greenoagh 2MONTANA62010
UnityOREGON52004
CobaltIDAHO42024
Howard Mdws.OREGON42019
Omak CreekWASHINGTON42021
Libby DamMONTANA32013
ClintonMONTANA32021
ChestnutMONTANA32022
GreenoughMONTANA32004
CusickWASHINGTON32024
West ThumbWYOMING31982
Horse CreekWYOMING32024
CoolinIDAHO22024
KalispellMONTANA21994
PolsonMONTANA22015
Pagil GulchMONTANA22024
Threemile WaMONTANA22023
FloraOREGON22001
LogdellOREGON22024
WickiupOREGON22024
TroyOREGON22021
Deer ParkWASHINGTON22009
Sullivan Lake 2WASHINGTON22023

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