Species · Massachusetts · BBS 2025 Release · 1966–2024

Barn Swallow Population Trend in Massachusetts

Barn Swallow in Massachusetts has declined: down 44% on the route-weighted index since 1968.

-44%Since 1968
32Routes In State
58Years

Notable Barn Swallow Trends in Massachusetts

No notable trend signals for Barn Swallow in Massachusetts. See the full index history below.

Barn Swallow Population Forecast in Massachusetts

If the recent trend holds, Barn Swallow in Massachusetts is projected to fall about 37% by 2029 — from 7.3 in 2024 to a central estimate of 4.6 (95% range 1.3–7.8). A 5-year backtest shows a typical error of ±15%, with 100% of held-out values landing inside the 95% band.

-37%Change by 2029
4.6Projected 2029 index
1.37.895% range
±15%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
20255.01.78.2
20264.91.68.1
20274.81.58.0
20284.71.47.9
20294.61.37.8

Barn Swallow Survey Routes in Massachusetts

Routes recording Barn Swallow in Massachusetts.
Pittsfield2320161967
Belchertown2120241967
Chilmark2019831969
Cummington 21620242015
Gay Head1420241996
Maynard1320221967
Chesterfield1320241967
Marion1120241966
Cummington920141968
Hancock920151997
Princeton819761969
E Pepperell819941966
Monterey820242019
Brockton720191967
Warren720091968
Littleton520231967
Mansfield520241968
S Barre520241968
Cheshire519941969
Ware River420221993
Wellfleet 2420242016
Holden420241977
Prattville320191966
Newburyport320211967
N Orange320241968

Barn Swallow Population Trend in Other States

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