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

Common Poorwill Population Trend in Idaho

All statesAerial insectivores

Common Poorwill in Idaho has collapsed: down 79% on the route-weighted index since 1987.

-79%Since 1987TrendPercent 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 →
13Routes 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 →
32YearsYears 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 IdahoNotable 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 →

Common Poorwill has collapsed in Idaho: down 79% on the route-weighted index since 1987.

Common Poorwill Population Forecast in Idaho

If the recent trend holds, Common Poorwill in Idaho is projected to stay roughly flat through 2024, near 0.04 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±112.6%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2024TrendPercent 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 2024 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1295% 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 →
±112.6%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 Idaho is projected to stay roughly flat through 2024, near 0.04 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±112.6%, with 100% of held-out values landing inside the 95% band.19772024
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 →
20200.040.000.13
20210.040.000.13
20220.040.000.12
20230.040.000.12
20240.040.000.12

Common Poorwill Survey Routes in Idaho

Routes recording Common Poorwill in Idaho.
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 →
Twin Buttes420011985
Lost River419951995
Almo320001997
Daniels Res120001992
Kyle Canyon119981998
Circular Bu120041995
Picabo120182013
Crane Creek120192005
Craters120172003
Springfield119771977
Triangle120131992
Magic Mtn119921991
Pocatello120141987

Common Poorwill Population Trend in Other States

arizonacaliforniacoloradokansasmontananebraskanevadanew-mexicooklahomaoregonsouth-dakotatexasutahwashingtonwyoming

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