BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Sooty Grouse Population Analysis

PhasianidaeGame birdsDendragapus fuliginosus

Sooty Grouse has surged: up 267% on the route-weighted index since 1970.

+267%Since 1970TrendPercent 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 →
128RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Sooty Grouse

The Sooty Grouse (Dendragapus fuliginosus) is a North American member of the Pheasants, Grouse & Turkeys (Phasianidae). In this analysis it is grouped with the game birds.

Size
12–47 in long (30–120 cm) — a ground-dwelling game bird (typical for the family)
Habitat
Fields, brushland, prairie and the forest floor, where it forages and nests on the ground.
Diet
Seeds, grain, buds, leaves and insects gathered on the ground.
Range
Recorded on 128 Breeding Bird Survey routes across 4 states, most concentrated in the Northern Pacific Rainforest.
Family
Phasianidae · Game birds

Notable Sooty Grouse TrendsNotable 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. See the full index history below.

Sooty Grouse Population Forecast

If the recent trend holds, Sooty Grouse is projected to stay roughly flat through 2030, near 0.04 (95% range 0.03–0.06). A 5-year backtest shows a typical error of ±25%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2030TrendPercent 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 →
0.04Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.03–0.0695% 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 →
±25%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 is projected to stay roughly flat through 2030, near 0.04 (95% range 0.03–0.06). A 5-year backtest shows a typical error of ±25%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20260.040.020.06
20270.040.020.06
20280.040.020.06
20290.040.030.06
20300.040.030.06

Where the Sooty Grouse Is Detected

BBS routes recording Sooty Grouse, sized by most recent count.

Sooty Grouse Population Trend by State

Sooty Grouse population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alaska-83%197515
California+68%197643
Oregon-80%197035
Washington+33%197135

Sooty Grouse Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Sooty Grouse population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Northern Pacific Rainforest+102%197081
Great Basin-31%197128
Sierra Nevada+49%197717

Sooty Grouse Conservation Status

Our route-weighted index shows it up about 267% since 1970.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.