BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Brown-headed Cowbird In Great Basin

All regionsGreat BasinGeneralists

Brown-headed Cowbird in Great Basin has edged up: up 19% on the route-weighted index since 1970.

+19%Since 1970
256Routes In Region
56Years

Notable Signals

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

Forecast

If the recent trend holds, Brown-headed Cowbird in Great Basin is projected to rise about 45% by 2029 — from 5.4 in 2024 to a central estimate of 7.9 (95% range 2.9–13). A 5-year backtest shows a typical error of ±64.2%, with 100% of held-out values landing inside the 95% band.

+45%Change by 2029
7.9Projected 2029 index
2.9–1395% range
±64.2%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
20258.02.913
20268.02.913
20277.92.913
20287.92.913
20297.92.913

Routes In Great Basin

Routes recording Brown-headed Cowbird in Great Basin.
DorrisCALIFORNIA2002019
UmatillaOREGON1152023
OthelloWASHINGTON521991
TwispWASHINGTON492024
NighthawkWASHINGTON422024
CedarvilleCALIFORNIA302024
Lake ChelanWASHINGTON292024
Columbia NwrWASHINGTON292022
Iron GateCALIFORNIA282019
Glenns FerryIDAHO271986
MesaWASHINGTON272008
IngallsCALIFORNIA252001
LeavenworthWASHINGTON252024
Ruby ValleyNEVADA242001
NewcastleUTAH242022
ArdenvoirWASHINGTON231987
KendallWASHINGTON232024
Mt HoodOREGON222024
Modoc Point 2OREGON222024
HarringtonWASHINGTON222012
Crowder FlatCALIFORNIA212019
Fandango CanOREGON212024
PicaboIDAHO202021
GardnervilleNEVADA192012
BuchananOREGON192024

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