- Minnesota Breeding Bird Distribution
- Breeding Habitat
- Population Abundance
- Literature Cited
A regular breeding resident and migrant. The Northern Rough-winged Swallow was uncommon during the Minnesota Breeding Bird Atlas (MNBBA).
Widely distributed from central British Columbia, east across the southern edge of the Canadian provinces and south throughout all of the United States. Sparsely distributed throughout its breeding range; a few small centers of abundance can be found in eastern Mississippi, southern Arizona, and in western Nevada (Figure 1).
Assigned a Continental Concern Score of 10/20 by Partners in Flight; designated a Species in Greatest Conservation Concern by the Minnesota Department of Natural Resources.
Medium-distance migrant that spends winters in southern California, along the Gulf coast of the United States, and in Central America.
Usually nests in burrows constructed by other species, including Belted Kingfishers, Bank Swallows, and small mammals. There are conflicting reports on whether the species excavates its own burrow. Breeding pairs may nest singly or in small groups consisting of a few pairs.
Described as a breeding resident throughout the state, Roberts’s (1932) only caveat was that he doubted whether the species occurred in the state’s Northwest Angle, remarking that the “conditions” there were not suited to the swallow’s needs. Presumably he was considering the absence of much elevation in the Angle’s broad, flat landscape dominated by aspen-birch forests and coniferous peatlands. There were, however, reliable reports from many northern regions, including the Red River valley, from Clay County north to Marshall County, as well as from the northwest corner of Kittson County, Itasca State Park, Cass County, and Itasca County. Breeding evidence (both confirmed and inferred nesting evidence) was available from 9 counties in southern and central Minnesota (Fillmore, Hennepin, Houston, McLeod, Pipestone, Rock, Sherburne, Wasbasha, and Washington) as well as from Leech Lake and Itasca State Park. Roberts’s brief account notes that although the species was common, it was less abundant than the Bank Swallow.
Forty years later, Green and Janssen’s (1975) updated account of the species’ distribution noted it was numerous in southern and central Minnesota and less numerous farther north, becoming scarce in the northeast. Several years later Janssen (1987) included a statewide distribution map that identified 20 counties, widely dispersed throughout the state, where nesting had been confirmed since 1970. Hertzel and Janssen (1998) later added an additional 6 counties to the list, all located from Aitkin County south.
The Minnesota Biological Survey has documented 197 breeding season locations of the Northern Rough-winged Swallow during its field surveys. More than half of the records were located from the Minnesota River valley south to the Iowa border (Minnesota Department of Natural Resources 2016).
During the MNBBA, observers reported 615 Northern Rough-winged Swallow records in 9.8% (465/4,743) of the surveyed atlas blocks and in 13.1% (306/2,337) of the priority blocks. Breeding was confirmed in 110 blocks (Figures 2 and 3; Table 1). Although the number of records was relatively small, the birds were observed in 83 of Minnesota’s 87 counties and were confirmed breeding in 59 counties. Thirty-six of the counties were new to the list published by Hertzel and Janssen (1998); 7 of the new counties were included because of blocks that crossed county lines (Big Stone, Cass, Itasca, Lac qui Parle, Renville, Yellow Medicine, and Washington). Found throughout the state, the majority of records were in southern Minnesota, from Big Stone County east through St. Cloud and Chisago County and further south. The Northern Rough-winged Swallow had the fewest total number of MNBBA records of the six members of the swallow family that breed in Minnesota.
The distribution and relative abundance of the Northern Rough-winged Swallow has changed little in Minnesota over the past 100 years. The state is near the northern periphery of the species’ breeding range, and the swallow is increasingly sparse as one moves north of the Brainerd Lakes region and Duluth. Elsewhere within its breeding range, records suggest the swallow may be expanding north in the Midwest and New England, and south along the Florida peninsula. Whether this represents a natural range expansion or is simply the result of better documentation of the species’ distribution by field observers is unknown (De Jong 1996). Anyone who has struggled to correctly identify swallows as they swiftly dart about on the wing appreciates the challenges of field identification. Even John James Audubon, in his first encounter with the bird, summarily dismissed them as Sand Swallows, now known as Bank Swallows, until tired by a long day, he sat down and shot a few and could clearly see their distinguishing features (Bent 1942).
*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.