- Minnesota Breeding Bird Distribution
- Breeding Habitat
- Population Abundance
- Literature Cited
A regular breeding species and migrant; regular in winter with reports from scattered locations statewide. The third most frequently reported species, the Red-winged Blackbird was very abundant during the Minnesota Breeding Bird Atlas (MNBBA).
Distributed across Canada, the United States, and portions of Central America, the core of the blackbird’s breeding range is in the northern Great Plains and east through the entire Mississippi River Valley south to the Texas Gulf Coast (Figure 1).
Assigned a Continental Concern Score of 8/20 by Partners in Flight.
A year-round resident or short-distance migrant. Most birds breeding in Canada and the northern United States migrate to the southern United States for the winter.
Feeds primarily on a variety of terrestrial insects during the summer and waste grain and seeds during the winter.
An open-cup nest secured to standing vegetation.
The Red-winged Blackbird was recognized as an abundant and widely distributed breeding species as early as 1892, when Hatch wrote the first comprehensive account of Minnesota birds (Hatch 1892). When Roberts published his more detailed account of the species in 1932, he reflected on the species abundance:
There is, perhaps, no more abundant and widely distributed native bird in North America than the Red-winged Blackbird, and Minnesota, with its thousands of lakes, marshes and sloughs, possesses an all too generous share.
Indeed, their abundance often wreaked havoc with farmers as the birds took a liking to young grain sprouts, ripened grain crops yet to be harvested, and ears of corn when the kernels are still soft and milky (Bent 1958). Late summer flocks were enormous in size. One observer wrote that, from a distance, they looked “like a dense cloud of black smoke,” flying so close to one another that a single shot could take down 60–70 birds (Roberts 1932). Roberts himself noted that the birds that come to roost at some of the state’s largest wetlands “are beyond computation,” comprised of “millions and millions” of birds.
Despite the extensive loss of wetlands throughout much of Minnesota, the extent of the species’ breeding distribution has remained essentially unchanged over the past 100 years. Green and Janssen (1975) simply noted that it was a resident statewide while Janssen (1987) described it as “one of the most common and evenly distributed breeding species in the state.” By 1998 it had been confirmed breeding in 53 of Minnesota’s 87 counties since the year 1970 (Hertzel and Janssen 1998).
Perhaps the most significant change in the species distribution has been the increasing number of birds observed during the winter months. Even in the early 1900s, large flocks of red-wings often remained in southern Minnesota during the winter season (Roberts 1932). But, over the years, winter observations gradually extended further north into northwestern, north central, and northeastern Minnesota. Now consistently observed in southern Minnesota during the winter, the number of birds overwintering in the northern counties varies considerably from year to year (Minnesota Ornithologists Union 2016).
The MNBBA reported a total of 9,496 Red-winged Blackbird records in 77.9% (3,843/4,934) of the atlas blocks that were surveyed and in 90.1% (2,106/2,338) of the 2,339 priority blocks. Breeding evidence was gathered in 26.5% (1,307) of the surveyed blocks and documented in all 87 Minnesota counties (Figures 2 and 3; Table 1). Although the species was found throughout the state, it was less abundant in the far northeast and north central regions. It was outnumbered during the atlas only by the American Robin (10,227 records) and the Common Yellowthroat (9,609 records).
Atlas data also were used to generate a model that predicts the relative abundance of the Red-winged Blackbird statewide (Figure 4). The species is most abundant south and west of the Laurentian Mixed Forest Province with predicted densities ranging from moderate to high. The species is considerably less abundant throughout most of the northern forest with the exception of small pockets of more suitable habitat that support higher breeding densities, especially in the extensive peatlands north of Red Lake.
*Note that the definition of confirmed nesting of a species is different for Breeding Bird Atlas projects, including the definition used by the Minnesota Breeding Bird Atlas, compared with a more restrictive definition used by the Minnesota Ornithologists’ Union. For details see the Data Methods Section.