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Species · West Virginia · BBS 2025 Release · 1966–2024

Worm-eating Warbler Population Trend in West Virginia

All statesForest birds

Worm-eating Warbler in West Virginia has declined: down 38% on the route-weighted index since 1968.

-38%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 →
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 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 rise about 40% by 2029 — from 0.54 in 2024 to a central estimate of 0.76 (95% range 0.18–1.3). A 5-year backtest shows a typical error of ±30.2%, with 100% of held-out values landing inside the 95% band.

+40%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 →
0.76Projected 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 →
0.18–1.395% 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 →
±30.2%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 rise about 40% by 2029 — from 0.54 in 2024 to a central estimate of 0.76 (95% range 0.18–1.3). A 5-year backtest shows a typical error of ±30.2%, 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 →
20250.760.181.3
20260.760.181.3
20270.760.181.3
20280.760.181.3
20290.760.181.3

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 →
Shanghai920221995
Hix620241970
Sleepy Creek619901966
Pedro320231979
Canaan320191976
Denmar320241990
Mo Of Seneca320241971
Monongah319981966
Josephs Mill320231995
Yellow Spg320221975
Bramwell220191978
Hanover220221984
Clear Creek220231992
Welch220222002
Arlee219751967
Nicut220191986
Fayetteville219961989
Strange Crk220231982
Washburn220221980
Mcdonald220031989
Albright219741966
Smoot120241980
Stollings120021995
Ghent120241978
Breeden120241994

Worm-eating Warbler Population Trend in Other States

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

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