BirdAnalyst
Species · Idaho · BBS 2026 Release · 1966–2025

Redhead Population Trend in Idaho

All statesWaterfowl

Redhead in Idaho has collapsed: down 90% on the route-weighted index since 1971.

-90%Since 1971TrendPercent 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 →
16Routes 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 →
43YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Redhead 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 →

Redhead has collapsed in Idaho: down 89% on the route-weighted index since 1971.

Redhead Population Forecast in Idaho

If the recent trend holds, Redhead in Idaho is projected to stay roughly flat through 2030, near 0.00 (95% range 0.00–1.6). A 5-year backtest shows a typical error of ±1247.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2030TrendPercent 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 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.695% 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 →
±1247.7%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, Redhead in Idaho is projected to stay roughly flat through 2030, near 0.00 (95% range 0.00–1.6). A 5-year backtest shows a typical error of ±1247.7%, with 100% of held-out values landing inside the 95% band.19692030
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 →
20260.000.001.6
20270.000.001.6
20280.000.001.6
20290.000.001.6
20300.000.001.6

Redhead Survey Routes in Idaho

Routes recording Redhead 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 →
Naples2320221981
Preston1819941991
Pasadena Val1619911988
Crane Creek720082008
Picabo620092000
Blacks Creek519741973
Iron Springs420191988
Blackft Res220031984
Twin Buttes219991999
Cabarton220222009
Springfield220151969
Cedar Hill120151999
Yellow Pine120122012
Magic Mtn120092009
Featherville120102010
Mud Lake120251992

Redhead Population Trend in Other States

alaskaarizonacaliforniacoloradoiowakansasmichiganminnesotamontananebraskanevadanew-mexiconew-yorknorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.