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

Brown-headed Cowbird Population Trend in Virginia

All statesGeneralists

Brown-headed Cowbird in Virginia has declined: down 29% on the route-weighted index since 1968.

-29%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 →
88Routes 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 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 Brown-headed Cowbird in Virginia. See the full index history below.

Brown-headed Cowbird Population Forecast in Virginia

If the recent trend holds, Brown-headed Cowbird in Virginia is projected to fall about 24% by 2030 — from 5.9 in 2025 to a central estimate of 4.5 (95% range 2.6–6.4). A 5-year backtest shows a typical error of ±28.4%, with 60% of held-out values landing inside the 95% band.

-24%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 →
4.5Projected 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 →
2.6–6.495% 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 →
±28.4%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 Virginia is projected to fall about 24% by 2030 — from 5.9 in 2025 to a central estimate of 4.5 (95% range 2.6–6.4). A 5-year backtest shows a typical error of ±28.4%, with 60% 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 →
20264.62.86.5
20274.62.76.5
20284.62.76.5
20294.62.76.4
20304.52.66.4

Brown-headed Cowbird Survey Routes in Virginia

Routes recording Brown-headed Cowbird in 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 →
Brandon3620251992
Chincoteag W2920221992
Backbay2419741966
Big Meadows2320251993
Ringgold2120251985
Branchville2120241966
Newsoms1920241967
Hebron1920221981
Carters Brdg 21920252015
Wylliesburg1420191971
Star Tannery1320251977
Church Road1320251966
Loft Mtn1320231993
Stanley1220251966
Quinby1220251966
Hebron 21120252023
Cornland1020141976
Amherst920251967
Big Island920251968
Concord920241967
Mannboro920251967
Pungo920251975
Pw Forest Pk920091992
Newville820241988
Walkers820231992

Brown-headed Cowbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontwashingtonwest-virginiawisconsinwyoming

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