- Minnesota Breeding Bird Distribution
- Breeding Habitat
- Population Abundance
- Literature Cited
A regular breeding species and migrant; observed during the winter months along the Mississippi River in southeast Minnesota and in scattered open-water locations in central Minnesota. The Canvasback was a rare species during the Minnesota Breeding Bird Atlas (MNBBA).
The breeding distribution of the Canvasback stretches from central Alaska south across the Prairie Provinces of Canada and the northern Great Plains of the United States. Western Minnesota is the eastern periphery of the species’ breeding range in the United States. Scattered populations are found to the east and west of the core breeding range. Breeding densities are highest in portions of Alaska, the northern Yukon and Northwest Territories, and the prairie potholes of Canada and north-central North Dakota. Its relative abundance within the federal Breeding Bird Survey (BBS) region is illustrated in Figure 1.
A game species, the Canvasback is assigned a Moderately High Continental Priority by the North American Waterfowl Management Plan. It has been assigned a Continental Concern Score of 10/20 by Partners in Flight.
A short- to medium-distance migrant that winters along the coasts of the United States and in the southern United States and northern Mexico.
A diving duck that feeds primarily on aquatic plants and aquatic invertebrates.
A platform constructed in emergent vegetation over shallow water; occasionally placed on the ground.
In 1932 Roberts wrote that the Canvasback, a species of the northern Great Plains, was formerly “a common summer resident” throughout the western region of the state.” At the time of his writing, he lamented that it had “almost entirely disappeared as a breeding bird,” although it continued to migrate through each spring and fall. He references a survey conducted by Breckenridge in June 1929, from Lincoln County in southwestern Minnesota, north to Kittson County in the northwest. Not a single Canvasback was sighted. Prior to this time, in the late 1800s, this handsome species was considered a regular summer resident at Heron Lake in southwestern Minnesota and in some of the larger, shallow wetland basins in northwestern Minnesota, such as Thief and Mud Lakes in Marshall County. Nesting had been confirmed at all three of these sites between 1896 and 1900. Roberts had also observed the birds in Minneapolis in early June 1925, which suggested they were breeding.
More than 40 years later, the Canvasback’s plight had improved considerably. Green and Janssen (1975) described it as a regular summer resident, restricted primarily to the northwestern region of the state, stretching from northwestern Becker County north to the Canadian border. Reports of nesting birds were occasionally documented, however, as far south as Le Sueur, Lincoln, and Lyon Counties, and as far east as Hennepin County.
A few years later, Jessen and Henderson (1979) reported that the summer of 1978 was the “best year for Canvasbacks breeding in Minnesota in recent history.” Jessen, a waterfowl specialist with the Minnesota Department of Natural Resources for many years, reported 699 young from 46 broods. All but 1 of the broods was reported in west-central and northwestern Minnesota; the 1 outlier was in Faribault County, in south-central Minnesota.
In 1987 Janssen included a statewide distribution map in his updated account of the species that identified all of western Minnesota as within the species’ breeding range, stretching east to Hennepin, Sherburne, and Wright Counties in the north, and Faribault County in the south. Noting once again that northwestern Minnesota constituted the core of the species’ range, Janssen reported that nesting had been confirmed since 1970 in 23 counties, from Faribault in the south, east to Hennepin, and north to Kittson. Hertzel and Janssen (1998) later added 4 additional counties to the map, all within the primary breeding range delineated by Janssen (1987).
As of 2015, the Minnesota Biological Survey had reported 46 breeding season locations for the Canvasback. The records were widely dispersed across the grasslands and aspen parklands of western Minnesota. The most eastern location was in northern Freeborn County (Minnesota Department of Natural Resources 2015).
During the MNBBA, participants documented 94 Canvasback reports from 1.6% (77/4,741) of the surveyed atlas blocks and from 1.6% (38/2,337) of the priority blocks. Breeding was confirmed in 24 of the surveyed blocks (Figures 2 and 3; Table 1). The birds were reported in 21 of Minnesota’s 87 counties, and breeding was confirmed in 11 counties, all within the species’ primary breeding range. Only 1 record was found south of the Minnesota River, in Freeborn County; other outliers were in northwestern Hennepin County (French Lake) and in northern Cass County (shallow northern bay of Leech Lake). Seven of the 24 confirmed breeding records were from Marshall County. Grant County was new to the list of confirmed breeding records compiled by Hertzel and Janssen (1998); all 3 reports in the county were of fledged young.
Although never abundant in Minnesota, Canvasbacks have made a significant comeback from the late 1800s, when Roberts (1932) considered them on the brink of extirpation. Beyond Minnesota, the species’ breeding distribution appears to be shifting farther to the northwest in Canada and Alaska, while the bird is becoming less common in the eastern portions of its breeding range in Canada (Mowbray 2002).
*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.