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Species · Indiana · BBS 2026 Release · 1966–2025

Brown-headed Cowbird Population Trend in Indiana

All statesGeneralists

Brown-headed Cowbird in Indiana has held roughly steady: up 3% on the route-weighted index since 1968.

+3%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 →
69Routes 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 IndianaNotable 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 Indiana. See the full index history below.

Brown-headed Cowbird Population Forecast in Indiana

If the recent trend holds, Brown-headed Cowbird in Indiana is projected to rise about 32% by 2030 — from 15 in 2025 to a central estimate of 20 (95% range 14–26). A 5-year backtest shows a typical error of ±29.9%, with 80% of held-out values landing inside the 95% band.

+32%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 →
20Projected 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 →
14–2695% 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 →
±29.9%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 Indiana is projected to rise about 32% by 2030 — from 15 in 2025 to a central estimate of 20 (95% range 14–26). A 5-year backtest shows a typical error of ±29.9%, 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 →
2026191325
2027191325
2028201326
2029201426
2030201426

Brown-headed Cowbird Survey Routes in Indiana

Routes recording Brown-headed Cowbird in Indiana.
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 →
Packertown5020041967
Newberry4320251999
Jamestown3220251986
Rensselaer3120251999
Kewanna3020221981
Ellis3020241966
Maplewood3020212000
Evansville2820221966
Georgia2820251999
W Lafayette2720251981
Frankfort2620251999
Witts Station2620252000
Knox2520251981
Fowler2520251966
Monticello2320251981
Thorntown2320251982
Sexton2320241981
Plainfield2319991999
Washington2220251987
Celestine2220251979
Wallace2220241999
Muncie2119971981
New Phila2120251982
Kokomo2120241993
Galveston2020251981

Brown-headed Cowbird Population Trend in Other States

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

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