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Species · Idaho · BBS 2026 Release · 1966–2025

Sage Thrasher Population Trend in Idaho

All statesArid-land birds

Sage Thrasher in Idaho has surged: up 79% on the route-weighted index since 1971.

+79%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 →
40Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Sage Thrasher 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 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 →

Sage Thrasher has surged in Idaho: up 79% on the route-weighted index since 1971.

Sage Thrasher Population Forecast in Idaho

If the recent trend holds, Sage Thrasher in Idaho is projected to rise about 84% by 2030 — from 5.2 in 2025 to a central estimate of 9.5 (95% range 3.9–15). A 5-year backtest shows a typical error of ±59%, with 80% of held-out values landing inside the 95% band.

+84%Change 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 →
9.5Projected 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 →
3.9–1595% 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 →
±59%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, Sage Thrasher in Idaho is projected to rise about 84% by 2030 — from 5.2 in 2025 to a central estimate of 9.5 (95% range 3.9–15). A 5-year backtest shows a typical error of ±59%, with 80% of held-out values landing inside the 95% band.19692030
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 →
20269.43.815
20279.43.915
20289.53.915
20299.53.915
20309.53.915

Sage Thrasher Survey Routes in Idaho

Routes recording Sage Thrasher 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 →
Dubois4120251969
Henry3119831973
Iron Springs2420241988
Sawtooth City 22220252015
Daniels Res2120251988
Kyle Canyon1620251985
Blacks Creek1620171969
Craters1520181979
Triangle1520251985
Blackft Res1320181984
Twin Buttes1320251985
Tractor Flat1220251985
Almo1220251988
Sawtooth Cty1220141988
Carey1120251989
Lost River820251985
Leadore720241974
Dougal Res420211988
Baker320241974
Magic Mtn320251990
Crane Creek320191988
Springfield220161977
Featherville220251992
Picabo220211988
Mud Lake220252004

Sage Thrasher Population Trend in Other States

arizonacaliforniacoloradomontananebraskanevadanew-mexiconorth-dakotaoregonsouth-dakotautahwashingtonwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.