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

Sora Population Trend in Colorado

All statesWetland birds

Sora in Colorado has surged: up 77% on the route-weighted index since 1976.

+77%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 →
39Routes 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 →
45YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Sora 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 →

Sora has surged in Colorado: up 77% on the route-weighted index since 1976.

Sora Population Forecast in Colorado

If the recent trend holds, Sora in Colorado is projected to stay roughly flat through 2029, near 0.10 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±23.3%, with 100% of held-out values landing inside the 95% band.

-4%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 →
0.10Projected 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 →
0.00–0.4295% 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 →
±23.3%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, Sora in Colorado is projected to stay roughly flat through 2029, near 0.10 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±23.3%, with 100% of held-out values landing inside the 95% band.19732029
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 →
20250.100.000.42
20260.100.000.42
20270.100.000.42
20280.100.000.42
20290.100.000.42

Sora Survey Routes in Colorado

Routes recording Sora 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 →
Walden320172017
Alamosa320241988
Yampa220161983
Colona219871983
Tarryall220192006
Castleton220231988
Doyleville220232004
Buffalo Park220231993
Deadman Rd.220211992
Fox Creek220242024
Maybell120151973
Buford120141987
Aspen119831983
Parlin120221977
Moffat120241973
Dolores119821976
Falfa119981977
Rio Grnds Rs120242002
Summitville120212000
Wray Gulch120051988
Wilson Creek120242024
Lost Lake120192002
Cortez 2120132013
Gordon Creek119951995
Dinosaur120242013

Sora Population Trend in Other States

alaskaarizonacaliforniaidahoillinoisindianaiowakansasmainemassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-dakotaohiooregonpennsylvaniasouth-dakotautahvermontwashingtonwisconsinwyoming

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