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

Field Sparrow Population Trend in West Virginia

All statesForest birds

Field Sparrow in West Virginia has declined: down 49% on the route-weighted index since 1968.

-49%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 →
64Routes 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 Field 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 →

No notable trend signals for Field Sparrow in West Virginia. See the full index history below.

Field Sparrow Population Forecast in West Virginia

If the recent trend holds, Field Sparrow in West Virginia is projected to fall about 36% by 2030 — from 7.3 in 2025 to a central estimate of 4.7 (95% range 1.6–7.7). A 5-year backtest shows a typical error of ±27%, with 100% of held-out values landing inside the 95% band.

-36%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 →
4.7Projected 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 →
1.6–7.795% 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 →
±27%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, Field Sparrow in West Virginia is projected to fall about 36% by 2030 — from 7.3 in 2025 to a central estimate of 4.7 (95% range 1.6–7.7). A 5-year backtest shows a typical error of ±27%, 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 →
20265.22.28.3
20275.12.08.1
20285.01.98.0
20294.81.87.9
20304.71.67.7

Field Sparrow Survey Routes in West Virginia

Routes recording Field 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 →
Nicut2720251986
Hix2320251970
Lost River2220251996
Mt Storm2119751966
Martinsburg2020251966
Mcdonald1920231987
Pt Pleasant1820251973
Bebee1620251972
Smoot1520251980
Slate1420251980
Ruthbelle1320251975
Shanghai1320251995
Pedro1220251979
Moundsville1220251972
Rockport1120251966
Yellow Spg1120231972
Rio1119951974
Berryburg1019961975
Denmar920251980
Albright919741966
Bismark920251976
Green Bank820251977
Sugar Grove820251966
Josephs Mill820241993
Paradise720251966

Field Sparrow Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawisconsinwyoming

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