BirdAnalyst
Species · BCR 19 · BBS 2025 Release · 1966–2024

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 13% on the route-weighted index since 1969.

-13%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 →
57YearsYears 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 2029, near 32 (95% range 24–41). A 5-year backtest shows a typical error of ±9.2%, with 100% of held-out values landing inside the 95% band.

+7%Change by 2029TrendPercent 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 2029 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 →
±9.2%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 2029, near 32 (95% range 24–41). A 5-year backtest shows a typical error of ±9.2%, with 100% of held-out values landing inside the 95% band.19672029
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 →
2025322441
2026322441
2027322441
2028322441
2029322441

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 →
KanopolisKANSAS1802024
CovertKANSAS1662024
SumnerNEBRASKA1662024
Berwyn 2NEBRASKA1082021
KenesawNEBRASKA1052024
Beloit 2KANSAS1042018
SurpriseNEBRASKA832024
LoganKANSAS802022
ChambersNEBRASKA782023
BerwynNEBRASKA722010
TableNEBRASKA712024
BartleyNEBRASKA632024
HamptonNEBRASKA632024
HanoverKANSAS612023
HunterOKLAHOMA602024
Swan LakeNEBRASKA572023
Wheeler CoNEBRASKA572024
SusankKANSAS552022
HendleyNEBRASKA552024
PhillipsburgKANSAS542022
HaysKANSAS512014
LibertyNEBRASKA512003
GrayKANSAS502019
SolomonKANSAS502019
DamarKANSAS502016

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.