BirdAnalyst
Species · BCR 24 · BBS 2026 Release · 1966–2025

Warbling Vireo In Central Hardwoods

All regionsCentral HardwoodsForest birds

Warbling Vireo in Central Hardwoods has surged: up 146% on the route-weighted index since 1968.

+146%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 →
130Routes 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 →
59YearsYears 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 →

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 →

Warbling Vireo has surged in Central Hardwoods: up 145% on the route-weighted index since 1968.

Warbling Vireo In Central Hardwoods Population Forecast

If the recent trend holds, Warbling Vireo in Central Hardwoods is projected to stay roughly flat through 2030, near 2.6 (95% range 1.7–3.4). A 5-year backtest shows a typical error of ±15.3%, with 100% of held-out values landing inside the 95% band.

+5%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 →
2.6Projected 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 →
1.7–3.495% 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 →
±15.3%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 Central Hardwoods is projected to stay roughly flat through 2030, near 2.6 (95% range 1.7–3.4). A 5-year backtest shows a typical error of ±15.3%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20262.51.63.3
20272.51.63.3
20282.51.73.4
20292.51.73.4
20302.61.73.4

Routes In Central Hardwoods

Routes recording Warbling Vireo in Central Hardwoods.
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 →
YorkILLINOIS132025
NewberryINDIANA132025
BrazilINDIANA112025
PleasurevillKENTUCKY112025
SpencerINDIANA102024
PlumKENTUCKY102025
Hodgenville 2KENTUCKY92023
BirdsILLINOIS82024
WashingtonINDIANA82025
Indian SpgsINDIANA82025
HudsonKENTUCKY82025
EastviewKENTUCKY82025
GlencoeKENTUCKY82018
BelknapILLINOIS72025
CumbackINDIANA72025
Clear SpringINDIANA72025
MerrimacKENTUCKY72024
JohnsonvilleKENTUCKY72021
Million 2KENTUCKY72024
BremenILLINOIS62025
RoyaltonILLINOIS62024
BoxvilleKENTUCKY61983
ShelbyvilleKENTUCKY61978
Buena VistaKENTUCKY62017
East UnionKENTUCKY62025

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