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

Red-winged Blackbird Population Trend in Colorado

All statesWetland birds

Red-winged Blackbird in Colorado has declined: down 32% on the route-weighted index since 1970.

-32%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 →
156Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Red-winged Blackbird 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 Red-winged Blackbird in Colorado. See the full index history below.

Red-winged Blackbird Population Forecast in Colorado

If the recent trend holds, Red-winged Blackbird in Colorado is projected to fall about 21% by 2030 — from 25 in 2025 to a central estimate of 20 (95% range 5.6–34). A 5-year backtest shows a typical error of ±8.8%, with 100% of held-out values landing inside the 95% band.

-21%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 →
20Projected 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 →
5.6–3495% 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 →
±8.8%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, Red-winged Blackbird in Colorado is projected to fall about 21% by 2030 — from 25 in 2025 to a central estimate of 20 (95% range 5.6–34). A 5-year backtest shows a typical error of ±8.8%, with 100% 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 →
2026227.736
2027217.236
2028216.635
2029206.135
2030205.634

Red-winged Blackbird Survey Routes in Colorado

Routes recording Red-winged Blackbird 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 →
Yampa25920231969
Prospect Val25320001992
Alamosa20120251988
Falfa16520251971
Prospect Valley 214020252001
Yellowjacket Pass13720251998
Dolores12319871968
Julesburg11220211998
Pagosa Spgs10319821968
Doyleville9820251988
Hudson9620251988
Powderhorn9520251994
Castleton9420251988
Amherst8920241992
Buford8320251970
Fort Morgan8220251996
Sheridan Lak8220161995
Fruita8120071988
Tarryall8120251988
Adams Co.7220221989
Paonia7220251992
Parlin6320251968
Last Chance 26220252017
Cortez 26220172009
Pleasant View6020212021

Red-winged Blackbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniaconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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