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Species · West Virginia · BBS 2026 Release · 1966–2025

Worm-eating Warbler Population Trend in West Virginia

All statesForest birds

Worm-eating Warbler in West Virginia has declined: down 35% on the route-weighted index since 1968.

-35%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 →
61Routes 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 →
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 Worm-eating Warbler Trends in West VirginiaNotable 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 Worm-eating Warbler in West Virginia. See the full index history below.

Worm-eating Warbler Population Forecast in West Virginia

If the recent trend holds, Worm-eating Warbler in West Virginia is projected to stay roughly flat through 2030, near 0.76 (95% range 0.19–1.3). A 5-year backtest shows a typical error of ±30.4%, with 100% of held-out values landing inside the 95% band.

-4%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 →
0.76Projected 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 →
0.19–1.395% 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 →
±30.4%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, Worm-eating Warbler in West Virginia is projected to stay roughly flat through 2030, near 0.76 (95% range 0.19–1.3). A 5-year backtest shows a typical error of ±30.4%, 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 →
20260.760.191.3
20270.760.191.3
20280.760.191.3
20290.760.191.3
20300.760.191.3

Worm-eating Warbler Survey Routes in West Virginia

Routes recording Worm-eating Warbler in West Virginia.
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 →
Hix1220251970
Sleepy Creek619901966
Denmar520251990
Shanghai420251995
Monongah319981966
Josephs Mill320231995
Yellow Spg320221975
Smoot220251980
Bramwell220191978
Hanover220221984
Clear Creek220231992
Welch220222002
Arlee219751967
Nicut220191986
Fayetteville219961989
Mo Of Seneca220251971
Mcdonald220031989
Albright219741966
Pedro120251979
Stollings120021995
Ghent120241978
Breeden120241994
Pt Pleasant120002000
Hubbardstown119661966
Spencer120221990

Worm-eating Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawaregeorgiaillinoisindianaiowakentuckylouisianamarylandmassachusettsmississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawisconsin

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