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

Brown-headed Cowbird Population Trend in West Virginia

All statesGeneralists

Brown-headed Cowbird in West Virginia has fallen sharply: down 71% on the route-weighted index since 1968.

-71%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 Brown-headed Cowbird 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 →

Brown-headed Cowbird has fallen sharply in West Virginia: down 71% on the route-weighted index since 1968.

Brown-headed Cowbird Population Forecast in West Virginia

If the recent trend holds, Brown-headed Cowbird in West Virginia is projected to fall about 72% by 2030 — from 4.2 in 2025 to a central estimate of 1.2 (95% range 0.00–7.4). A 5-year backtest shows a typical error of ±79.4%, with 80% of held-out values landing inside the 95% band.

-72%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 →
1.2Projected 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 →
0.00–7.495% 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 →
±79.4%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, Brown-headed Cowbird in West Virginia is projected to fall about 72% by 2030 — from 4.2 in 2025 to a central estimate of 1.2 (95% range 0.00–7.4). A 5-year backtest shows a typical error of ±79.4%, 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 →
20262.00.008.2
20271.80.008.0
20281.60.007.8
20291.40.007.6
20301.20.007.4

Brown-headed Cowbird Survey Routes in West Virginia

Routes recording Brown-headed Cowbird 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 →
Stollings3820211986
Henderson3020232002
Cedarville1920231982
Sleepy Creek1519901966
Albright1419741966
Mcdonald1320231987
Bismark1220251976
Welch1120231980
Paradise1120251966
Yellow Spg1120221972
Hix1020251970
Josephs Mill1020241993
Bramwell920251978
Smoot820251980
Sutton820251976
Ringgold820252025
Fayetteville719961980
Three Forks720251971
Slate720251981
Rio719951974
Meadland620251997
Olcott620241966
Richwood620251980
Mt Storm619751966
Lost River620251996

Brown-headed Cowbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwisconsinwyoming

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