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

Chestnut-sided Warbler Population Trend in West Virginia

All statesForest birds

Chestnut-sided Warbler in West Virginia has surged: up 454% on the route-weighted index since 1968.

+454%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 →
41Routes 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 Chestnut-sided 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 →

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 →

Chestnut-sided Warbler has surged in West Virginia: up 454% on the route-weighted index since 1968.

Chestnut-sided Warbler Population Forecast in West Virginia

If the recent trend holds, Chestnut-sided Warbler in West Virginia is projected to stay roughly flat through 2030, near 2.7 (95% range 1.7–3.8). A 5-year backtest shows a typical error of ±29.9%, with 80% 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 →
2.7Projected 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 →
1.7–3.895% 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 →
±29.9%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, Chestnut-sided Warbler in West Virginia is projected to stay roughly flat through 2030, near 2.7 (95% range 1.7–3.8). A 5-year backtest shows a typical error of ±29.9%, with 80% 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 →
20262.61.63.6
20272.61.63.7
20282.71.63.7
20292.71.63.7
20302.71.73.8

Chestnut-sided Warbler Survey Routes in West Virginia

Routes recording Chestnut-sided 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 →
Valley Head4320251966
Green Bank1520251977
Bemis1120252001
Richwood1020251980
Bismark920251976
Glady820252001
Clear Creek720011999
Smoot520251986
Bowden420241993
Canaan420251974
Hanover320011998
Lost River320232023
Three Forks320251971
Dailey320251973
Moundsville319781975
Meadowville320251972
Mt Storm319731966
Glade Run 2320252003
Pedro220251979
Bramwell220231980
Glade Run220021988
Mo Of Seneca220241980
Albright219741967
Yellow Spg220231993
Hix120251972

Chestnut-sided Warbler Population Trend in Other States

alabamaarkansascoloradoconnecticutgeorgiaillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotanevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandtennesseevermontvirginiawisconsinwyoming

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