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Species · Utah · BBS 2025 Release · 1966–2024

Plumbeous Vireo Population Trend in Utah

All statesForest birds

Plumbeous Vireo in Utah has surged: up 217% on the route-weighted index since 1972.

+217%Since 1972TrendPercent 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 →
73Routes 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 →
51YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Plumbeous Vireo 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 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 →

Plumbeous Vireo has surged in Utah: up 217% on the route-weighted index since 1972.

Plumbeous Vireo Population Forecast in Utah

If the recent trend holds, Plumbeous Vireo in Utah is projected to rise about 49% by 2029 — from 0.97 in 2024 to a central estimate of 1.4 (95% range 0.75–2.1). A 5-year backtest shows a typical error of ±68.9%, with 60% of held-out values landing inside the 95% band.

+49%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 →
1.4Projected 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 →
0.75–2.195% 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 →
±68.9%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, Plumbeous Vireo in Utah is projected to rise about 49% by 2029 — from 0.97 in 2024 to a central estimate of 1.4 (95% range 0.75–2.1). A 5-year backtest shows a typical error of ±68.9%, with 60% of held-out values landing inside the 95% band.19702029
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 →
20251.40.682.1
20261.40.702.1
20271.40.722.1
20281.40.732.1
20291.40.752.1

Plumbeous Vireo Survey Routes in Utah

Routes recording Plumbeous Vireo 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 →
Gooseberry920241994
Main Canyon920241991
Alton 2820242021
Alton720191997
Bryce Canyon720241990
Boulder620191986
Fayette420211992
Uintah Nf419941988
Notom420211998
Dixie Nf320241994
Lake Powell320041995
Beck 2320181990
Vernal320122005
Wellington319971997
Newcastle320221997
Beryl320241987
Book Ridge220232003
Beaver220241980
Aneth220242001
La Sal220001993
Shivwitz220121992
Hatch220241994
Pine Creek220192001
Monticello220241998
Wasatch Nf219961996

Plumbeous Vireo Population Trend in Other States

arizonacaliforniacoloradoidahomontananebraskanevadanew-mexicosouth-dakotatexaswyoming

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