Species · Massachusetts · BBS 2025 Release · 1966–2024
Mourning Warbler Population Trend in Massachusetts
Mourning Warbler in Massachusetts has edged down: down 18% on the route-weighted index since 1987.
-18%Since 1987
4Routes In State
13Years
Notable Mourning Warbler Trends in Massachusetts
No notable trend signals for Mourning Warbler in Massachusetts. See the full index history below.
Mourning Warbler Survey Routes in Massachusetts
| Hancock | 1 | 2012 | 2010 |
| Cummington | 1 | 1998 | 1975 |
| Chesterfield | 1 | 2015 | 1987 |
| Pittsfield | 1 | 2001 | 1975 |
Mourning Warbler Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.