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

Sagebrush Sparrow Population Trend in Colorado

All statesGeneralists

Sagebrush Sparrow in Colorado has increased: up 40% on the route-weighted index since 1976.

+40%Since 1976TrendPercent 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 →
28Routes 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 →
40YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Sagebrush Sparrow Trends in ColoradoNotable 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 Sagebrush Sparrow in Colorado. See the full index history below.

Sagebrush Sparrow Population Forecast in Colorado

If the recent trend holds, Sagebrush Sparrow in Colorado is projected to fall about 39% by 2029 — from 0.84 in 2024 to a central estimate of 0.52 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±25.1%, with 100% of held-out values landing inside the 95% band.

-39%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 →
0.52Projected 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 →
0.00–1.295% 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 →
±25.1%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, Sagebrush Sparrow in Colorado is projected to fall about 39% by 2029 — from 0.84 in 2024 to a central estimate of 0.52 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±25.1%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.530.001.2
20260.520.001.2
20270.520.001.2
20280.520.001.2
20290.520.001.2

Sagebrush Sparrow Survey Routes in Colorado

Routes recording Sagebrush Sparrow in Colorado.
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 →
Browns Park2420241992
Mosca1920241993
Basin1420241995
Mesita820242021
Antonito820041995
San Luis620241995
Yampa520231990
Doyleville419891989
Maybell320241975
Great Divide220242013
Wray Gulch219891989
Dinosaur220241996
Alamosa220241995
Angora219991998
Mesaverde Np120002000
Douglas Pass120242013
Rosevale120222017
Abarr119761976
Parlin119951993
Moffat120031974
Falfa120031999
Wilson Creek120171992
Lay120191996
Baxter Pass120242024
Ragged Mtn.119961996

Sagebrush Sparrow Population Trend in Other States

arizonacaliforniaidahomontananevadanew-mexicooregonutahwashingtonwyoming

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