BirdAnalyst
Species · BCR 28 · BBS 2025 Release · 1966–2024

Warbling Vireo In Appalachian Mountains

All regionsAppalachian MountainsForest birds

Warbling Vireo in Appalachian Mountains has held roughly steady: up 3% on the route-weighted index since 1968.

+3%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 →
256Routes 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 Warbling Vireo in Appalachian Mountains. See the full index history below.

Forecast

If the recent trend holds, Warbling Vireo in Appalachian Mountains is projected to stay roughly flat through 2029, near 1.0 (95% range 0.74–1.3). A 5-year backtest shows a typical error of ±8.4%, with 100% of held-out values landing inside the 95% band.

-4%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 →
1.0Projected 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 →
0.74–1.395% 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 →
±8.4%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, Warbling Vireo in Appalachian Mountains is projected to stay roughly flat through 2029, near 1.0 (95% range 0.74–1.3). A 5-year backtest shows a typical error of ±8.4%, 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 →
20251.00.731.3
20261.00.731.3
20271.00.741.3
20281.00.741.3
20291.00.741.3

Routes In Appalachian Mountains

Routes recording Warbling Vireo in Appalachian Mountains.
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 →
MeridaleNEW-YORK242024
BloomsburyNEW-JERSEY132024
CobleskillNEW-YORK112023
MilfordNEW-YORK112023
RamseysburgNEW-JERSEY92024
McdonoughNEW-YORK92017
CorbettsvileNEW-YORK92024
GreentownPENNSYLVANIA92024
Mt HopeNEW-YORK82010
MedusaNEW-YORK82024
DrydenNEW-YORK82024
S Berne 2NEW-YORK72024
WaterstreetPENNSYLVANIA72024
MartinsburgWEST-VIRGINIA72024
SmithsburgMARYLAND62014
HopeNEW-JERSEY61994
AdamsvilleOHIO61989
Yellow SpgWEST-VIRGINIA62022
RiftonNEW-YORK51986
DurhamNEW-YORK51976
E NewarkNEW-YORK52024
GainesvilleNEW-YORK52023
CattaraugusNEW-YORK52019
CentervilleNEW-YORK52015
OmegaOHIO52024

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