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

Sharp-tailed Grouse Population Trend in Idaho

All statesGeneralists

Sharp-tailed Grouse in Idaho has collapsed: down 90% on the route-weighted index since 1990.

-90%Since 1990TrendPercent 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 →
4Routes 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 →
19YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Sharp-tailed Grouse Trends in IdahoNotable 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 declinecomputed 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 →

Sharp-tailed Grouse has collapsed in Idaho: down 90% on the route-weighted index since 1990.

Sharp-tailed Grouse Population Forecast in Idaho

If the recent trend holds, Sharp-tailed Grouse in Idaho is projected to stay roughly flat through 2023, near 0.00 (95% range 0.00–0.19). A 5-year backtest shows a typical error of ±349.8%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2023TrendPercent 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 →
0.00Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1995% 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 →
±349.8%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, Sharp-tailed Grouse in Idaho is projected to stay roughly flat through 2023, near 0.00 (95% range 0.00–0.19). A 5-year backtest shows a typical error of ±349.8%, with 100% of held-out values landing inside the 95% band.19882023
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 →
20190.000.000.19
20200.000.000.19
20210.000.000.19
20220.000.000.19
20230.000.000.19

Sharp-tailed Grouse Survey Routes in Idaho

Routes recording Sharp-tailed Grouse in Idaho.
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 →
Blackft Res220012001
Crane Creek120052003
Bates120182016
Daniels Res120151988

Sharp-tailed Grouse Population Trend in Other States

alaskacoloradomichiganminnesotamontananebraskanorth-dakotasouth-dakotautahwashingtonwisconsinwyoming

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