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Species · Washington · BBS 2025 Release · 1966–2024

Sooty Grouse Population Trend in Washington

All statesGeneralists

Sooty Grouse in Washington has edged up: up 12% on the route-weighted index since 1971.

+12%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 →
34Routes 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 →
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 Sooty Grouse Trends in WashingtonNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Sooty Grouse in Washington. See the full index history below.

Sooty Grouse Population Forecast in Washington

If the recent trend holds, Sooty Grouse in Washington is projected to rise about 169% by 2029 — from 0.16 in 2024 to a central estimate of 0.42 (95% range 0.05–0.80). A 5-year backtest shows a typical error of ±73.9%, with 100% of held-out values landing inside the 95% band.

+169%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 →
0.42Projected 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 →
0.05–0.8095% 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 →
±73.9%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, Sooty Grouse in Washington is projected to rise about 169% by 2029 — from 0.16 in 2024 to a central estimate of 0.42 (95% range 0.05–0.80). A 5-year backtest shows a typical error of ±73.9%, 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 →
20250.420.050.79
20260.420.050.79
20270.420.050.79
20280.420.050.79
20290.420.050.80

Sooty Grouse Survey Routes in Washington

Routes recording Sooty Grouse in Washington.
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 →
No Cascades820191988
Mt. Adams820231993
Cougar520231976
Packwood420111975
Cascade Riv320061988
Mt Rainier320211991
Ozette220241974
Montesand220241990
Ronald220232015
Ellensburg220182011
Mazama220102010
Pe Ell219971995
Greenwater220242024
Newhalem120231968
Taholah120121976
Kamilche120052005
E. Mt. Adams120241997
Bunker Hill120021968
Rimrock120231973
Kendall120031986
Glacier120241976
Raymond 2120232023
Mendota119811980
Index 2120232018
White Chuck120191994

Sooty Grouse Population Trend in Other States

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