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Species · Nevada · BBS 2025 Release · 1966–2024

Bell's Vireo Population Trend in Nevada

All statesForest birds

Bell's Vireo in Nevada has declined: down 33% on the route-weighted index since 1996.

-33%Since 1996TrendPercent 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 →
4Routes 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 Bell's Vireo 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 →

No notable trend signals for Bell's Vireo in Nevada. See the full index history below.

Bell's Vireo Population Forecast in Nevada

If the recent trend holds, Bell's Vireo in Nevada is projected to fall about 76% by 2029 — from 0.21 in 2024 to a central estimate of 0.05 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±77.5%, with 100% of held-out values landing inside the 95% band.

-76%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 →
0.05Projected 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 →
0.00–0.2795% 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 →
±77.5%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, Bell's Vireo in Nevada is projected to fall about 76% by 2029 — from 0.21 in 2024 to a central estimate of 0.05 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±77.5%, with 100% of held-out values landing inside the 95% band.19942029
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 →
20250.060.000.28
20260.060.000.28
20270.060.000.27
20280.050.000.27
20290.050.000.27

Bell's Vireo Survey Routes in Nevada

Routes recording Bell's Vireo 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 →
Meadow Vally520241996
Nelson120022002
Ash Meadows120241994
Hiko120072002

Bell's Vireo Population Trend in Other States

arizonaarkansascaliforniacoloradoillinoisindianaiowakansaskentuckymichiganminnesotamissourinebraskanew-mexiconorth-dakotaohiooklahomasouth-dakotatexasutahwisconsin

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