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

Vesper Sparrow Population Trend in West Virginia

All statesGrassland birds

Vesper Sparrow in West Virginia has collapsed: down 96% on the route-weighted index since 1968.

-96%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 →
24Routes 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 →
46YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Vesper Sparrow 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 declinecomputed 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 →

Vesper Sparrow has collapsed in West Virginia: down 96% on the route-weighted index since 1968.

Vesper Sparrow Population Forecast in West Virginia

If the recent trend holds, Vesper Sparrow in West Virginia is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±539.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.00Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.4195% 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 →
±539.4%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, Vesper Sparrow in West Virginia is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.41). A 5-year backtest shows a typical error of ±539.4%, with 100% of held-out values landing inside the 95% band.19662028
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 →
20240.000.000.41
20250.000.000.41
20260.000.000.41
20270.000.000.41
20280.000.000.41

Vesper Sparrow Survey Routes in West Virginia

Routes recording Vesper Sparrow 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 →
Sleepy Creek419811968
Smoot319861986
Pedro220081994
Canaan220232015
Green Bank220041978
Slate219831983
Albright219741966
Hix120131970
Glade Run119901990
Ghent119811980
Welch120172017
Bemis120152002
Bismark119871987
Valley Head119851966
Sugar Grove119781966
Mo Of Seneca119851970
Moundsville119801972
Monongah119951966
Bebee119941972
Greer119801966
Yellow Spg119731972
Martinsburg120151966
Clinton119831966
Ruthbelle120011976

Vesper Sparrow Population Trend in Other States

arizonacaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsinwyoming

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