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Species · Arizona · BBS 2026 Release · 1966–2025

Hutton's Vireo Population Trend in Arizona

All statesForest birds

Hutton's Vireo in Arizona has surged: up 138% on the route-weighted index since 1977.

+138%Since 1977TrendPercent 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Hutton's Vireo Trends in ArizonaNotable 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 increasecomputed 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 →

Hutton's Vireo has surged in Arizona: up 138% on the route-weighted index since 1977.

Hutton's Vireo Population Forecast in Arizona

If the recent trend holds, Hutton's Vireo in Arizona is projected to fall about 34% by 2030 — from 0.56 in 2025 to a central estimate of 0.37 (95% range 0.12–0.63). A 5-year backtest shows a typical error of ±117.9%, with 80% of held-out values landing inside the 95% band.

-34%Change 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 →
0.37Projected 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 →
0.12–0.6395% 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 →
±117.9%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, Hutton's Vireo in Arizona is projected to fall about 34% by 2030 — from 0.56 in 2025 to a central estimate of 0.37 (95% range 0.12–0.63). A 5-year backtest shows a typical error of ±117.9%, with 80% of held-out values landing inside the 95% band.19752030
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 →
20260.360.100.61
20270.360.110.62
20280.360.110.62
20290.370.110.62
20300.370.120.63

Hutton's Vireo Survey Routes in Arizona

Routes recording Hutton's Vireo in Arizona.
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 →
Portal920251975
Tonto Vill.620251994
Patagonia420251989
Carr Mtn420181987
Rucker320091993
Prescott220251975
Peña Blanca220251987
Sunizona119771977
Dragoon120001996
Bartlett Res120102010
Alpine119961996
Sunizona 2120192001
Mt. Graham120231999
Aztec Peak119771977
Sprucedale120072006

Hutton's Vireo Population Trend in Other States

californianew-mexicooregontexaswashington

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