Species · Utah · BBS 2025 Release · 1966–2024

Brown-headed Cowbird Population Trend in Utah

Brown-headed Cowbird in Utah has increased: up 39% on the route-weighted index since 1970.

+39%Since 1970
108Routes In State
56Years

Notable Brown-headed Cowbird Trends in Utah

No notable trend signals for Brown-headed Cowbird in Utah. See the full index history below.

Brown-headed Cowbird Population Forecast in Utah

If the recent trend holds, Brown-headed Cowbird in Utah is projected to rise about 10% by 2029 — from 2.4 in 2024 to a central estimate of 2.6 (95% range 0.00–9.0). A 5-year backtest shows a typical error of ±53.2%, with 100% of held-out values landing inside the 95% band.

+10%Change by 2029
2.6Projected 2029 index
0.009.095% range
±53.2%Backtest error
19682029
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
20252.80.009.2
20262.80.009.2
20272.70.009.1
20282.70.009.1
20292.60.009.0

Brown-headed Cowbird Survey Routes in Utah

Routes recording Brown-headed Cowbird in Utah.
Woodruff2720242002
Newcastle2420221997
Randolph2020241992
Bear River1520231992
Beck1319871969
Johnson Can1320241988
Fish Springs1319871987
Wellington 21220112003
Delta1020241987
Leamington1020161992
Kelton919951993
Hardware Ranch920181998
Wendover819971974
Moquith Mtn820241987
Promontory720241969
Jensen720241992
Hanna720241997
Wellington720021998
Wellington 3620242012
Goose Creek Mtn.620231997
Pine Creek620231998
Castleton519851970
Bonanza520081992
Lost Cr. Res520171995
Hyrum419751975

Brown-headed Cowbird Population Trend in Other States

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