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Species · BCR 14 · BBS 2026 Release · 1966–2025

Philadelphia Vireo In Atlantic Northern Forest

All regionsAtlantic Northern ForestForest birds

Philadelphia Vireo in Atlantic Northern Forest has declined: down 35% on the route-weighted index since 1969.

-35%Since 1969TrendPercent 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 →
77Routes In RegionSurvey 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 SignalsNotable 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 Philadelphia Vireo in Atlantic Northern Forest. See the full index history below.

Philadelphia Vireo In Atlantic Northern Forest Population Forecast

If the recent trend holds, Philadelphia Vireo in Atlantic Northern Forest is projected to stay roughly flat through 2030, near 0.22 (95% range 0.06–0.39). A 5-year backtest shows a typical error of ±549.7%, with 40% of held-out values landing inside the 95% band.

n/aChange 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 →
0.22Projected 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 →
0.06–0.3995% 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 →
±549.7%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, Philadelphia Vireo in Atlantic Northern Forest is projected to stay roughly flat through 2030, near 0.22 (95% range 0.06–0.39). A 5-year backtest shows a typical error of ±549.7%, with 40% of held-out values landing inside the 95% band.19672030
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 →
20260.210.040.38
20270.220.050.39
20280.220.050.39
20290.220.050.39
20300.220.060.39

Routes In Atlantic Northern Forest

Routes recording Philadelphia Vireo in Atlantic Northern Forest.
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 →
AshlandMAINE112008
WashburnMAINE91993
BethelMAINE62021
CharlestonMAINE52019
Big TwentyMAINE52007
Baker LakeMAINE51994
Northfield 2MAINE52022
Heron LakeMAINE52003
AuroraMAINE42010
Clayton LakeMAINE42001
BrooksMAINE32021
Moose RiverMAINE32005
Forest StaMAINE31985
InletNEW-YORK32005
MedwayMAINE21994
HudsonMAINE22009
LudlowMAINE21983
YankeetuladiMAINE22009
NesowadnehunMAINE22021
Jefferson HlNEW-HAMPSHIRE22025
Blue Ridge SNEW-YORK21988
BiddefordMAINE12006
Wilson MillsMAINE12012
GreenwoodMAINE12016
ReedsMAINE12022

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