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

Redhead Population Trend in Utah

All statesWaterfowl

Redhead in Utah has collapsed: down 86% on the route-weighted index since 1986.

-86%Since 1986TrendPercent 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 →
21Routes 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 →
38YearsYears 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 UtahNotable 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 Utah: down 85% on the route-weighted index since 1986.

Redhead Population Forecast in Utah

If the recent trend holds, Redhead in Utah is projected to stay roughly flat through 2030, near 0.06 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±211.2%, 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 →
0.06Projected 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 →
0.00–2.095% 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 →
±211.2%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 Utah is projected to stay roughly flat through 2030, near 0.06 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±211.2%, 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 →
20260.180.002.1
20270.150.002.1
20280.120.002.1
20290.090.002.0
20300.060.002.0

Redhead Survey Routes in Utah

Routes recording Redhead in Utah.
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 →
Bear River3120231993
Hatch820032003
Oak City619961988
Promontory420111986
Goshen420091998
Beck319861986
Callao320241992
La Sal 2220062006
Navajo Lake219931969
Lynn220211983
M Warner Res220252001
Castle Dale220152015
Hardware Ranch219951995
Neponset Res120171998
E. Bear Lake120121995
Notch Peak119931993
Boulder120061992
Randolph120251992
Bicknell120181997
Gold Hill120221991
Main Canyon120101999

Redhead Population Trend in Other States

alaskaarizonacaliforniacoloradoidahoiowakansasmichiganminnesotamontananebraskanevadanew-mexiconew-yorknorth-dakotaoklahomaoregonsouth-dakotatexaswashingtonwisconsinwyoming

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