BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Brown-headed Cowbird In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionGeneralists

Brown-headed Cowbird in Prairie Hardwood Transition has edged down: down 24% on the route-weighted index since 1968.

-24%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 →
161Routes 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 Prairie Hardwood Transition. See the full index history below.

Brown-headed Cowbird In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Brown-headed Cowbird in Prairie Hardwood Transition is projected to stay roughly flat through 2029, near 15 (95% range 11–19). A 5-year backtest shows a typical error of ±4.4%, 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 →
15Projected 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 →
11–1995% 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 →
±4.4%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 Prairie Hardwood Transition is projected to stay roughly flat through 2029, near 15 (95% range 11–19). A 5-year backtest shows a typical error of ±4.4%, with 100% of held-out values landing inside the 95% band.19662029
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 →
2025151119
2026151119
2027151119
2028151119
2029151119

Routes In Prairie Hardwood Transition

Routes recording Brown-headed Cowbird in Prairie Hardwood Transition.
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 →
GrimmsWISCONSIN962021
Sherburne NrMINNESOTA542024
PardeevilleWISCONSIN542024
PackertownINDIANA502004
Le CenterMINNESOTA492023
AnnatonWISCONSIN482024
KnappMINNESOTA472024
New LondonMINNESOTA442024
Pt WashingtnWISCONSIN432024
WhitewaterMINNESOTA412000
ParisWISCONSIN412024
HebronWISCONSIN362024
GuilfordILLINOIS352023
KielWISCONSIN352022
RichmondMICHIGAN342024
MinnetonkaMINNESOTA332024
WeyerhauserWISCONSIN332024
Brook ParkMINNESOTA322024
CumberlandWISCONSIN322024
KewannaINDIANA302022
EllisINDIANA302024
HartlandMICHIGAN302011
Hazel GreenWISCONSIN302024
St CharlesMICHIGAN292019
Bell OakMICHIGAN292008

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