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Species · Pennsylvania · BBS 2025 Release · 1966–2024

White-eyed Vireo Population Trend in Pennsylvania

All statesForest birds

White-eyed Vireo in Pennsylvania has risen sharply: up 65% on the route-weighted index since 1968.

+65%Since 1968TrendPercent 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 →
70Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable White-eyed Vireo Trends in PennsylvaniaNotable 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 →

White-eyed Vireo has risen sharply in Pennsylvania: up 65% on the route-weighted index since 1968.

White-eyed Vireo Population Forecast in Pennsylvania

If the recent trend holds, White-eyed Vireo in Pennsylvania is projected to rise about 17% by 2029 — from 0.17 in 2024 to a central estimate of 0.20 (95% range 0.05–0.34). A 5-year backtest shows a typical error of ±46.4%, with 100% of held-out values landing inside the 95% band.

+17%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 →
0.20Projected 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 →
0.05–0.3495% 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 →
±46.4%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, White-eyed Vireo in Pennsylvania is projected to rise about 17% by 2029 — from 0.17 in 2024 to a central estimate of 0.20 (95% range 0.05–0.34). A 5-year backtest shows a typical error of ±46.4%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.200.050.34
20260.200.050.34
20270.200.050.34
20280.200.050.34
20290.200.050.34

White-eyed Vireo Survey Routes in Pennsylvania

Routes recording White-eyed Vireo in Pennsylvania.
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 →
New Ringgold920241983
Berwick520031992
West Grove519961966
Eldred320132008
Rasselas319711969
Jefferson320241966
N Washington220212021
Little Marsh220111993
Duvall220211974
Kaylor220211995
Rector219771977
Margaret220171988
Schwenksvill220221991
Mill Run220031978
Shrewsbury220141995
Jacobus220181986
Mifflintown220121977
Carsonville219911991
Espyville120131997
Clover120211991
Harmonsburg120232023
Ellenton119931993
Wyalusing119971997
Teepleville120242024
Wild Creek120162000

White-eyed Vireo Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinebraskanew-jerseynew-yorknorth-carolinaohiooklahomarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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