BirdAnalyst
Species · BCR 22 · BBS 2025 Release · 1966–2024

Brown-headed Cowbird In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieGeneralists

Brown-headed Cowbird in Eastern Tallgrass Prairie has risen sharply: up 72% on the route-weighted index since 1968.

+72%Since 1968
277Routes In Region
58Years

Notable Signals

long arc increasecomputed index

Brown-headed Cowbird has risen sharply in Eastern Tallgrass Prairie: up 72% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Brown-headed Cowbird in Eastern Tallgrass Prairie is projected to stay roughly flat through 2029, near 23 (95% range 20–27). A 5-year backtest shows a typical error of ±7.2%, with 100% of held-out values landing inside the 95% band.

+4%Change by 2029
23Projected 2029 index
20–2795% range
±7.2%Backtest error
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 index95% low95% high
2025231927
2026231927
2027231927
2028231927
2029232027

Routes In Eastern Tallgrass Prairie

Routes recording Brown-headed Cowbird in Eastern Tallgrass Prairie.
LincolnvilleKANSAS1332024
NorborneMISSOURI982023
BelleviewILLINOIS822024
MilfordMISSOURI662024
ChandlervillILLINOIS652024
FairlandILLINOIS562024
MurdockNEBRASKA532024
FrontenacMINNESOTA502024
Rock ValleyIOWA492024
LyonsNEBRASKA492024
MonticelloILLINOIS482024
SenecaKANSAS482022
College SpgsIOWA472004
PiersonIOWA472019
Ash CreekMINNESOTA472024
MadisonMISSOURI472024
Kahoka2MISSOURI472024
Cedar ValleyIOWA461997
StillwellILLINOIS452024
RensselaerMISSOURI452024
Grape CreekILLINOIS442024
ThrallKANSAS441970
Mill CreekILLINOIS432024
Terre HauteILLINOIS432024
KearneyMISSOURI432024

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