Species · Massachusetts · BBS 2025 Release · 1966–2024

Green Heron Population Trend in Massachusetts

Green Heron in Massachusetts has edged down: down 22% on the route-weighted index since 1969.

-22%Since 1969
28Routes In State
55Years

Notable Green Heron Trends in Massachusetts

No notable trend signals for Green Heron in Massachusetts. See the full index history below.

Green Heron Population Forecast in Massachusetts

If the recent trend holds, Green Heron in Massachusetts is projected to rise about 140% by 2029 — from 0.07 in 2024 to a central estimate of 0.16 (95% range 0.00–0.46). A 5-year backtest shows a typical error of ±100.3%, with 80% of held-out values landing inside the 95% band.

+140%Change by 2029
0.16Projected 2029 index
0.000.4695% range
±100.3%Backtest error
19672029
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
20250.170.000.47
20260.170.000.46
20270.170.000.46
20280.160.000.46
20290.160.000.46

Green Heron Survey Routes in Massachusetts

Routes recording Green Heron in Massachusetts.
Pittsfield420051988
Newburyport320111970
S Barre220231970
N. Andover220181995
Warren 2220122012
E Dennis120161973
Chilmark119751969
Marion120131969
Wellfleet120051970
Prattville120171968
Brockton119961969
Maynard120181968
Littleton120211970
N Oxford120122008
Mansfield120071993
Princeton119721972
E Pepperell119931967
Belchertown120151996
Warren120081970
N Orange120141972
Cummington119861969
Chesterfield120051971
Cheshire119941972
Sheffield120081975
Cape Cod Ns119921991

Green Heron Population Trend in Other States

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