Breeding Bird Atlas 2 Species Accounts
- Very widespread and likely increasing
- Action/monitoring needed
Bird species that breed in disturbed forest have a friend in humankind. This illustrates an interesting aspect of people’s relationship with other species. Birds and other organisms that can thrive in maturing wooded suburban landscapes and parks, despite the fragmentation caused by roads and the introduction of human-associated predators, are doing well in the current landscape of Massachusetts. The Rose-breasted Grosbeak is iconic in this category. The species was historically found in parks, wooded backyards, along shady suburban roadways, and in landscaped cemeteries, and today the Massachusetts range of this bird seems to be increasing because of the changes we have wrought upon the landscape. Despite this, however, the possibility of a quiet decline in this handsome species should not be discounted.
Historic StatusBeautifully plumed and decidedly mellifluous in song, the Rose-Breasted Grosbeak is a bird whose population has had its ups and downs. Forbush believed the species’ numbers grew during the 1800s in Massachusetts. Denizens of deciduous forests, they adapted well to the creation of farmland, so much so that they were sometimes known to specialize on the larvae of the Colorado potato beetle (Forbush 1927). On the other hand, the targeting of cultivated peas and fruits, and the buds and flowers of trees by this species labeled it as a sometimes pest. During the early 1900s, it was the beautiful voice of the Rose-breasted Grosbeak that condemned it, as it became a popular cage bird in its wintering range during that period (Bent 1968). The cage trade now long over, in the modern era it seems to have adapted well to suburbanization.
Atlas 1 DistributionRose-breasted Grosbeaks were widespread in Atlas 1, finding homes in 63% of the blocks surveyed, with particularly noteworthy concentrations in the western part of the state. The Marble Valleys reported evidence of breeding Rose-breasted Grosbeaks in every single block; in fact, no region west of the Worcester Plateau had less than 70% block occupancy. The Worcester Plateau had somewhat fewer occupied blocks than the surrounding regions, but still had a widely distributed Rose-breasted Grosbeak presence. The grosbeaks were fairly widespread throughout the Coastal Plains and Hills, but were fewer in the Bristol/Narragansett Lowlands, and almost absent from the Cape and Islands. The forests of Pitch Pine and scrub oak in the southeast likely failed to meet the needs of the grosbeaks, which prefer moist, mixed woods with occasional openings and a stronger deciduous component.
Atlas 2 Distribution and ChangeMaturing suburban landscapes and forests likely aided the expansion of Rose-breasted Grosbeaks during the Atlas interval, and their block occupancy shot up to 73%. The westernmost ecoregions were near saturation during Atlas 1, and remained so in Atlas 2. The Connecticut River Valley and the regions eastward showed notable gains for this species, especially the Worcester Plateau. Throughout the Coastal Plains, new Rose-breasted Grosbeak blocks were easy to come by, and losses were concentrated along the border with the Bristol/Narragansett Lowlands. The Bristol/Narragansett Lowlands and Cape Cod and the Islands showed only small net increases.
Atlas 1 Map
Atlas 2 Map
Atlas Change Map
|Atlas 1||Atlas 2||Change|
|Ecoregion||# Blocks||% Blocks||% of Range||# Blocks||% Blocks||% of Range||Change in # Blocks||Change in % Blocks|
|Marble Valleys/Housatonic Valley||39||100.0||6.4||34||87.2||4.5||-5||-12.8|
|Lower Berkshire Hills||27||96.4||4.4||23||74.2||3.0||-4||-14.8|
|Connecticut River Valley||47||83.9||7.7||60||92.3||7.9||5||10.4|
|Lower Worcester Plateau||57||77.0||9.4||77||96.3||10.2||6||11.1|
|S. New England Coastal Plains and Hills||186||68.9||30.5||243||85.9||32.2||26||11.5|
|Bristol and Narragansett Lowlands||44||41.5||7.2||50||43.9||6.6||4||4.0|
|Cape Cod and Islands||12||8.8||2.0||18||12.5||2.4||4||3.3|