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.Ī common inhabitant of wetland habitats, the Red-winged Blackbird is not particularly choosey, except to avoid the interior of dense forest stands.
The species is most abundant south and west of the Laurentian Mixed Forest Province with predicted densities ranging from moderate to high. It was outnumbered during the atlas only by the American Robin (10,227 records) and the Common Yellowthroat (9,609 records).Ītlas data also were used to generate a model that predicts the relative abundance of the Red-winged Blackbird statewide (Figure 4). Although the species was found throughout the state, it was less abundant in the far northeast and north central regions. 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). 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. 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). But, over the years, winter observations gradually extended further north into northwestern, north central, and northeastern Minnesota.
Even in the early 1900s, large flocks of red-wings often remained in southern Minnesota during the winter season ( Roberts 1932). Perhaps the most significant change in the species distribution has been the increasing number of birds observed during the winter months. 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). 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.ĭespite 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. 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). Late summer flocks were enormous in size.
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). 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. When Roberts published his more detailed account of the species in 1932, he reflected on the species abundance: 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).
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