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

Bald Eagle Population Trend in Colorado

All statesGeneralists

Bald Eagle in Colorado has increased: up 40% on the route-weighted index since 1984.

+40%Since 1984TrendPercent 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 →
36Routes 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 →
27YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Bald Eagle 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 Bald Eagle in Colorado. See the full index history below.

Bald Eagle Population Forecast in Colorado

If the recent trend holds, Bald Eagle in Colorado is projected to fall about 22% by 2029 — from 0.10 in 2024 to a central estimate of 0.08 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±57.8%, with 80% of held-out values landing inside the 95% band.

-22%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 →
0.08Projected 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 →
0.00–0.1695% 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 →
±57.8%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, Bald Eagle in Colorado is projected to fall about 22% by 2029 — from 0.10 in 2024 to a central estimate of 0.08 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±57.8%, with 80% of held-out values landing inside the 95% band.19702029
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 →
20250.080.000.15
20260.080.000.16
20270.080.000.16
20280.080.000.16
20290.080.000.16

Bald Eagle Survey Routes in Colorado

Routes recording Bald Eagle 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 →
Buford320242003
Arsenal 2320242016
Wildhorse L320192019
Maybell220121970
Dolores219841983
Walden220192015
Neegrande220182017
Yampa120212017
Harmony120242019
Arsenal120152001
Last Chance120132013
Falfa120232023
Rio Grnds Rs120192016
Wray Gulch120231995
Hudson120222016
Cortez 2120162010
Animas 2120162015
Tarryall120222022
Castleton120232023
Doyleville120162009
Guffey120242006
Lay120212016
Nunn120192017
Fort Morgan120212002
Julesburg120192016

Bald Eagle Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniaconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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