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

Common Poorwill Population Trend in Colorado

All statesAerial insectivores

Common Poorwill in Colorado has edged down: down 16% on the route-weighted index since 1972.

-16%Since 1972TrendPercent 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 →
35Routes 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 →
47YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Common Poorwill 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 Common Poorwill in Colorado. See the full index history below.

Common Poorwill Population Forecast in Colorado

If the recent trend holds, Common Poorwill in Colorado is projected to fall about 50% by 2029 — from 0.08 in 2024 to a central estimate of 0.04 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±43.7%, with 80% of held-out values landing inside the 95% band.

-50%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 →
0.04Projected 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 →
0.00–0.0995% 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 →
±43.7%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, Common Poorwill in Colorado is projected to fall about 50% by 2029 — from 0.08 in 2024 to a central estimate of 0.04 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±43.7%, with 80% of held-out values landing inside the 95% band.19682029
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 →
20250.040.000.09
20260.040.000.09
20270.040.000.09
20280.040.000.09
20290.040.000.09

Common Poorwill Survey Routes in Colorado

Routes recording Common Poorwill 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 →
Great Divide220222010
Uncompahgre220241990
Lay220242000
Gold Hill 2220242024
Deadman Rd.220051992
Maybell120211975
Yampa119861986
Briggsdale119681968
Mesaverde Np120232023
Douglas Pass119971997
Kiowa120131988
Delta120092009
Mica Butte119821972
Gilpin119711971
Wray Gulch120161992
Wilson Creek120041996
Willow Peak120171997
Dinosaur120022002
Doyleville120062006
Baxter Pass120241994
Powderhorn120221997
Browns Park120151997
Dunckley Pas120091998
Buffalo Park120232006
Flattops120152013

Common Poorwill Population Trend in Other States

arizonacaliforniaidahokansasmontananebraskanevadanew-mexicooklahomaoregonsouth-dakotatexasutahwashingtonwyoming

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