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

Virginia Rail Population Trend in Idaho

All statesWetland birds

Virginia Rail in Idaho has fallen sharply: down 55% on the route-weighted index since 1989.

-55%Since 1989TrendPercent 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 →
8Routes 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 →
19YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Virginia Rail 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 →

Virginia Rail has fallen sharply in Idaho: down 55% on the route-weighted index since 1989.

Virginia Rail Population Forecast in Idaho

If the recent trend holds, Virginia Rail in Idaho is projected to stay roughly flat through 2023, near 0.03 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±55%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2023TrendPercent 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 →
0.03Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0895% 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 →
±55%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, Virginia Rail in Idaho is projected to stay roughly flat through 2023, near 0.03 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±55%, with 80% of held-out values landing inside the 95% band.19772023
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 →
20190.030.000.08
20200.030.000.08
20210.030.000.08
20220.030.000.08
20230.030.000.08

Virginia Rail Survey Routes in Idaho

Routes recording Virginia Rail 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 →
Magic Mtn219991999
Naples120181988
Cedar Hill120032003
Almo119951995
Preston119941994
Squirrel119771977
Featherville119901990
Picabo119931989

Virginia Rail Population Trend in Other States

arizonacaliforniacoloradoconnecticutdelawareillinoisindianaiowakansasmainemarylandmassachusettsmichiganminnesotamontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotautahvermontvirginiawashingtonwisconsinwyoming

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