BirdAnalyst
Species · BCR 30 · BBS 2025 Release · 1966–2024

Brown-headed Cowbird In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastGeneralists

Brown-headed Cowbird in New England / Mid-Atlantic Coast has risen sharply: up 54% on the route-weighted index since 1968.

+54%Since 1968
164Routes In Region
58Years

Notable Signals

long arc increasecomputed index

Brown-headed Cowbird has risen sharply in New England / Mid-Atlantic Coast: up 54% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Brown-headed Cowbird in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2029, near 11 (95% range 8.7–13). A 5-year backtest shows a typical error of ±11%, with 80% of held-out values landing inside the 95% band.

+8%Change by 2029
11Projected 2029 index
8.7–1395% range
±11%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
2025108.412
2026108.512
2027118.612
2028118.613
2029118.713

Routes In New England / Mid-Atlantic Coast

Routes recording Brown-headed Cowbird in New England / Mid-Atlantic Coast.
Jones BeachNEW-YORK442013
WillimanticCONNECTICUT342018
MadisonMARYLAND342024
CokesburyMARYLAND342024
MysticCONNECTICUT302023
Chincoteag WVIRGINIA292022
HolleyvilleDELAWARE272004
Island CreekMARYLAND272024
Block IslandRHODE-ISLAND272010
La PlataMARYLAND242009
Forest GroveMARYLAND242023
HarringtonDELAWARE232024
HolmansvilleNEW-JERSEY222009
Spraguetown 2NEW-JERSEY212007
BlackbirdDELAWARE202024
DavidsnvilleMARYLAND202024
PomonaNEW-JERSEY202024
MarionMASSACHUSETTS192024
BrandonVIRGINIA192024
Holleyville 2DELAWARE182024
Milton 2DELAWARE182017
Tall TimbersMARYLAND182014
SinepuxentMARYLAND181978
FrankfordDELAWARE172012
MillingtonMARYLAND172024

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