BirdAnalyst
Species · Colorado · BBS 2026 Release · 1966–2025

White-crowned Sparrow Population Trend in Colorado

All statesForest birds

White-crowned Sparrow in Colorado has surged: up 557% on the route-weighted index since 1970.

+557%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 →
75Routes 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 White-crowned 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 →

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 →

White-crowned Sparrow has surged in Colorado: up 557% on the route-weighted index since 1970.

White-crowned Sparrow Population Forecast in Colorado

If the recent trend holds, White-crowned Sparrow in Colorado is projected to rise about 13% by 2030 — from 5.1 in 2025 to a central estimate of 5.8 (95% range 3.2–8.3). A 5-year backtest shows a typical error of ±61.4%, with 60% of held-out values landing inside the 95% band.

+13%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 →
5.8Projected 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 →
3.2–8.395% 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 →
±61.4%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, White-crowned Sparrow in Colorado is projected to rise about 13% by 2030 — from 5.1 in 2025 to a central estimate of 5.8 (95% range 3.2–8.3). A 5-year backtest shows a typical error of ±61.4%, with 60% 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 →
20265.42.97.9
20275.53.08.0
20285.63.18.1
20295.73.18.2
20305.83.28.3

White-crowned Sparrow Survey Routes in Colorado

Routes recording White-crowned 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 →
Stillwater Pass 27720252010
Willow Peak4720251988
Tincup4020251992
Heeney 23620252025
Stillwater Pass3520091998
Castleton3120251988
Steamboat L.3120251996
Lake City3120031988
Red Cliff2920251989
Flattops2920251992
Ragged Mtn.2720251994
Yampa2620231969
Weston Pass 22520252001
Dunckley Pas2520251992
Mount Evans2220241996
Heeney2120192017
Buffalo Park2020251992
Weston Pass1920001994
Lizard Head Pass1620252001
Trail Ridge Road1420142003
Walden1320251991
Guanella Pas1120251992
Como1020251994
Groundhog Rs1020251992
Westcliffe1019981998

White-crowned Sparrow Population Trend in Other States

alaskacaliforniaidahomontananevadanew-mexicooregonutahwashingtonwyoming

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