BirdAnalyst
Species · BCR 19 · BBS 2026 Release · 1966–2025

Brown-headed Cowbird In Central Mixed Grass Prairie

All regionsCentral Mixed Grass PrairieGeneralists

Brown-headed Cowbird in Central Mixed Grass Prairie has edged down: down 12% on the route-weighted index since 1969.

-12%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 →
130Routes In RegionSurvey 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 SignalsNotable 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 Central Mixed Grass Prairie. See the full index history below.

Brown-headed Cowbird In Central Mixed Grass Prairie Population Forecast

If the recent trend holds, Brown-headed Cowbird in Central Mixed Grass Prairie is projected to stay roughly flat through 2030, near 32 (95% range 24–41). A 5-year backtest shows a typical error of ±7.7%, 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 →
32Projected 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 →
24–4195% 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 →
±7.7%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 Central Mixed Grass Prairie is projected to stay roughly flat through 2030, near 32 (95% range 24–41). A 5-year backtest shows a typical error of ±7.7%, 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 →
2026332441
2027332441
2028332441
2029322441
2030322441

Routes In Central Mixed Grass Prairie

Routes recording Brown-headed Cowbird in Central Mixed Grass Prairie.
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 →
CovertKANSAS1972025
SurpriseNEBRASKA1382025
SumnerNEBRASKA1362025
KanopolisKANSAS1332025
Berwyn 2NEBRASKA1222025
Beloit 2KANSAS1042018
KenesawNEBRASKA742025
HamptonNEBRASKA732025
BerwynNEBRASKA722010
BelvidereNEBRASKA702025
HanoverKANSAS642025
HunterOKLAHOMA602024
BrownleeNEBRASKA592025
ChambersNEBRASKA572025
SusankKANSAS552022
PetersburgNEBRASKA522025
HaysKANSAS512014
HollenbergKANSAS512025
LibertyNEBRASKA512003
BradyNEBRASKA512025
GrayKANSAS502019
DamarKANSAS502016
KennedyNEBRASKA502025
PhillipsburgKANSAS482025
SolomonKANSAS482025

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