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

Redhead Population Trend in Nevada

All statesWaterfowl

Redhead in Nevada has fallen sharply: down 52% on the route-weighted index since 1971.

-52%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 →
15Routes 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 →
44YearsYears 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 NevadaNotable 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 fallen sharply in Nevada: down 52% on the route-weighted index since 1971.

Redhead Population Forecast in Nevada

If the recent trend holds, Redhead in Nevada is projected to fall about 100% by 2029 — from 0.25 in 2024 to a central estimate of 0.00 (95% range 0.00–22). A 5-year backtest shows a typical error of ±235.2%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–2295% 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 →
±235.2%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 Nevada is projected to fall about 100% by 2029 — from 0.25 in 2024 to a central estimate of 0.00 (95% range 0.00–22). A 5-year backtest shows a typical error of ±235.2%, with 100% 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 →
20250.000.0022
20260.000.0022
20270.000.0022
20280.000.0022
20290.000.0022

Redhead Survey Routes in Nevada

Routes recording Redhead in Nevada.
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 →
Ruby Valley 21020212021
Hiko719731973
Cortez620241968
Eureka520172009
Dobbin Creek420171971
Bald Mtn.320231992
Fallon319951992
Virgin Creek220151995
Toiyabe Nf220182018
Gardnerville220112001
Sheldon Nwr120012001
Rye Patch119711971
Ash Meadows120241993
Illipah119991999
Gardnerville 2120182018

Redhead Population Trend in Other States

alaskaarizonacaliforniacoloradoidahoiowakansasmichiganminnesotamontananebraskanew-mexiconew-yorknorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwisconsinwyoming

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