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

Dusky Grouse Population Trend in Utah

All statesGeneralists

Dusky Grouse in Utah has declined: down 36% on the route-weighted index since 1998.

-36%Since 1998TrendPercent 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 →
13Routes 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 →
22YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Dusky Grouse Trends in UtahNotable 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 Dusky Grouse in Utah. See the full index history below.

Dusky Grouse Population Forecast in Utah

If the recent trend holds, Dusky Grouse in Utah is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±137.3%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.02Projected 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 →
0.00–0.0695% 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 →
±137.3%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, Dusky Grouse in Utah is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.06). A 5-year backtest shows a typical error of ±137.3%, with 100% of held-out values landing inside the 95% band.19942029
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 →
20250.020.000.06
20260.020.000.06
20270.020.000.06
20280.020.000.06
20290.020.000.06

Dusky Grouse Survey Routes in Utah

Routes recording Dusky Grouse in Utah.
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 →
Saleratus Cr420052005
Alton 2120242021
Lost Cr. Res120121998
Ant Flat-Ogden Can120092009
Red Spur Mtn.120122012
La Sal 2120062006
Bryce Canyon120212021
La Sal 3120182008
Fish Lake Nf120161996
Navajo Lake120011996
Main Canyon120062006
Soapstone120121996
Moon Lake119941994

Dusky Grouse Population Trend in Other States

arizonacoloradoidahomontananevadanew-mexicooregonwashingtonwyoming

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