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Species · Missouri · BBS 2026 Release · 1966–2025

Brown-headed Cowbird Population Trend in Missouri

All statesGeneralists

Brown-headed Cowbird in Missouri has edged up: up 19% on the route-weighted index since 1969.

+19%Since 1969TrendPercent 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 →
95Routes 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 →
58YearsYears 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 MissouriNotable 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 Missouri. See the full index history below.

Brown-headed Cowbird Population Forecast in Missouri

If the recent trend holds, Brown-headed Cowbird in Missouri is projected to stay roughly flat through 2030, near 21 (95% range 14–28). A 5-year backtest shows a typical error of ±8.8%, with 100% of held-out values landing inside the 95% band.

+8%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 →
21Projected 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 →
14–2895% 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 →
±8.8%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 Missouri is projected to stay roughly flat through 2030, near 21 (95% range 14–28). A 5-year backtest shows a typical error of ±8.8%, with 100% of held-out values landing inside the 95% band.19672030
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 →
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Brown-headed Cowbird Survey Routes in Missouri

Routes recording Brown-headed Cowbird in Missouri.
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 →
Norborne9820232006
Miller9820252014
Lucerne8920252016
Hayti5720212016
Syracuse5320241969
Madison4720241971
Kahoka24720242002
Deventer4020251967
Warren3919831967
New Point3920251994
Frankford3720251985
Centertown3520251973
Palace3520252013
Rueter 23420252023
Kingsville3320251992
Rockingham3220251969
Hamilton3119851972
Clementine 23120072005
Akers3020251967
Sni Mills3019901967
Tarkio3019891968
Eugene3020252013
Bolckow2919921967
Lincoln2920252013
Gerald2920252013

Brown-headed Cowbird Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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