- Minnesota Breeding Bird Distribution
- Breeding Habitat
- Population Abundance
- Literature Cited
A regular breeding species and migrant; not reported every winter but is a winter visitant some years, when only one or a few birds are reported during the entire season. The Yellow-headed Blackbird was a common species during the Minnesota Breeding Bird Atlas (MNBBA).
Restricted primarily to western North America, stretching only as far east as the Great Lakes, the core of the Yellow-headed Blackbird’s breeding range is in the Prairie Potholes of central North Dakota (Figure 1).
Assigned a Continental Concern Score of 9/20 by Partners in Flight. Designated a Species in Greatest Conservation Need by the Minnesota Department of Natural Resources and a Target Conservation Species by Audubon Minnesota.
A medium-distance migrant wintering in the southern United States and Mexico.
Diet is composed primarily of insects during the breeding season, foraging on the ground or at the water’s surface; seeds and waste grain are consumed the remainder of the year.
An open-cup nest secured to emergent, wetland vegetation; frequently breeds in large colonies.
In the early 1900s, Roberts (1932) considered the Yellow-headed Blackbird to be a common summer resident throughout the “open country” of the western grasslands. Although this constituted its primary range, it also could be found along the perimeters of the northern forest wherever suitable wetlands were present. Indeed, nesting colonies were found as far north as Leech Lake in Cass County, at the mouth of the Rainy River in Lake of the Woods County, and near Duluth in St. Louis County. Confirmed nesting reports (nests with eggs) were available from 8 counties: Big Stone, Hennepin, Jackson, Kittson, Marshall, Otter Tail, Polk, and Sherburne. Inferred nesting reports (nest building) were available from Goodhue and Nobles Counties.
More than forty years later little had changed. Green and Janssen (1975) described nearly an identical breeding distribution, further clarifying the species’ absence from most of northeastern Minnesota, including Itasca and Koochiching Counties in north-central Minnesota and Pine and Aitkin Counties immediately to the south. A few years later, Janssen (1987) reported the species appeared to be expanding its range into the northeast region of the state. There even were June records documented from Cook County but these were presumed to be summer vagrants. In 1998, Hertzel and Janssen documented a total of 42 counties where Yellow-headed Blackbirds had been confirmed nesting since 1970, ten more than Janssen had identified in 1987.
A similar distribution was documented by the Minnesota Biological Survey, although no breeding season locations were found in the Arrowhead’s northeastern counties (Minnesota Department of Natural Resources 2016).
During the MNBBA, participants reported 1,426 Yellow-headed Blackbirds records in 16.8% (800/4,753) of the atlas blocks that were surveyed and in 20.5% (480/2,337) of the priority blocks. Breeding was confirmed in 110 blocks (Figures 2 and 3; Table 1). The birds were reported from all but 8 of Minnesota’s 87 counties: 4 in northeastern Minnesota and 4 in southeastern Minnesota. Breeding was confirmed in 47 counties; Red Lake County was included because of a block that straddled both Pennington and Red Lake Counties. Eighteen counties were additions to the list compiled by Hertzel and Janssen in 1998: Blue Earth, Carver, Chippewa, Cottonwood, Dakota, Douglas, Faribault, Freeborn, Isanti, McLeod, Murray, Nicollet, Norman, Polk, Otter Tail, Sibley, Swift, and Traverse. The species was most frequently reported from the central and southern regions of the Prairie Parklands Province.
Historically few changes have been documented in the species’ breeding range, with the exception that some accounts suggest it may be slowly spreading eastward For example, breeding populations in the Great Lakes regions were not documented until the mid-1900s, and the number of reports further east and as far south as Florida have increased in recent years (Twedt and Crawford 1995). In Minnesota, the species’ breeding range seems relatively unchanged in the past 100 years. Although there are a few summer reports from far northern St. Louis and Cook Counties, the species is still quite rare in the northeastern and north-central regions of the state.
Atlas data were also used to generate a model that predicts the relative abundance of Yellow-headed Blackbirds across the state (Figure 4). Tightly associated with suitable emergent wetlands, the species is predicted to be most abundant in the west-central and southwestern regions of the Prairie Parkland province with densities declining rapidly further north and east of the province.
*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.