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

Short-eared Owl Population Trend in Colorado

All statesGeneralists

Short-eared Owl in Colorado has fallen sharply: down 69% on the route-weighted index since 1974.

-69%Since 1974TrendPercent 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 →
24Routes 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 →
24YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Short-eared Owl 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 declinecomputed 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 →

Short-eared Owl has fallen sharply in Colorado: down 69% on the route-weighted index since 1974.

Short-eared Owl Population Forecast in Colorado

If the recent trend holds, Short-eared Owl in Colorado is projected to fall about 100% by 2029 — from 0.05 in 2024 to a central estimate of 0.00 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±61.1%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–0.0795% 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 →
±61.1%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, Short-eared Owl in Colorado is projected to fall about 100% by 2029 — from 0.05 in 2024 to a central estimate of 0.00 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±61.1%, with 100% 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 →
20250.000.000.07
20260.000.000.07
20270.000.000.07
20280.000.000.07
20290.000.000.07

Short-eared Owl Survey Routes in Colorado

Routes recording Short-eared Owl 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 →
Timpas420052005
Great Divide320242015
Fleming320061980
Cheyenne320092005
Pinneo219801980
Last Chance219831983
Maybell120171974
Arsenal120051993
Briggsdale120022002
Arsenal 2120242024
Abarr119801972
Moffat119851970
Hudson120242024
Waverly120152005
Adams Co.120112000
Gordon Creek119931993
Fort Morgan120052005
Campo120182000
Ellicott120162016
Karval120022001
Stoneham120102002
Amherst120141992
Haswell120052005
Neegrande120061998

Short-eared Owl Population Trend in Other States

alaskacaliforniaidahoillinoisiowakansasmarylandmichiganminnesotamontananebraskanevadanorth-dakotaohiooklahomaoregonsouth-dakotautahwashingtonwisconsinwyoming

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