Black-backed Woodpecker

A permanent resident, migrant, and winter visitant primarily in northern forested areas of the state. The Black-backed Woodpecker was uncommon during the Minnesota Breeding Bird Atlas (MNBBA).

Found in patches across Canada from Labrador to British Columbia and Alaska, southward into the Rocky Mountains and the eastern portion of the Cascades to northern California. In the midwestern and northeastern United States, it is found in the extreme northern portions (Figure 1).

Assigned a Continental Concern Score of 9/20 by Partners in Flight; identified as a Species in Greatest Conservation Need by the Minnesota Department of Natural Resources.

Permanent resident with southward movements in some years.

A specialist on wood-boring beetles (Cerambycidae), which it extracts by scaling and pecking the bark of trees, especially those in areas affected by fire, wind, or other disturbances.

Excavates a hole in trees of many different species.

Roberts (1932) described the Black-backed Woodpecker as “common in summer only in the northern third of the state but has been found in limited numbers in the nesting season as far south as Lake Mille Lacs, Aitkin County.” Roberts noted nesting activity of the species in Becker County (nest with young) and Itasca State Park (feeding young) and reported that many nests were found by Peabody and Warren on the Mesabi Iron Range in upper St. Louis County. He also described a “nest with eggs in a tamarack swamp near Lake Minnetonka” in May 9, 1891, as the “only breeding record south of the evergreen forests.” Later, Green and Janssen (1975) labeled this record as suspect because it was not observed firsthand by Roberts.

Green and Janssen (1975) described the Black-backed Woodpecker’s breeding range as extending as far west as Becker County and south to Crow Wing County. The species was most numerous in Lake and Cook Counties. They included confirmed nesting in 5 counties: Becker, Clearwater, Cook, Lake, and St. Louis. Inferred nesting was indicated in Crow Wing County. Several years later, Janssen (1987) classified the species as a “rare to locally uncommon resident in the northeast and northcentral regions.” He emphasized that Black-backed Woodpeckers were better represented in these areas in winter rather than summer, likely due to migrational movements in the fall and an exodus in the spring. Janssen (1987) identified confirmed nesting in 8 counties since 1970: Beltrami, Clearwater, Cook, Hubbard, Itasca, Lake, Lake of the Woods, and St. Louis. In their updated account, Hertzel and Janssen (1998) identified 7 counties with confirmed nesting since 1970, excluding Hubbard County.

The Minnesota Biological Survey (MBS) recorded 139 breeding season locations of the Black-backed Woodpecker during their county inventories (Minnesota Department of Natural Resources 2016). These locations were distributed from northeastern Becker County, Clearwater County, and northwestern Todd County to Cook County. Single locations were also noted in southern Aitkin, southern Pine, and northern Carlton Counties. The bulk of the observations were noted in Cook County and northern Lake and St. Louis Counties.

Participants in the MNBBA documented 158 records of the Black-backed Woodpecker. The records were distributed as far west as Marshall County, south to Aitkin and Crow Wing Counties, and northeast to Cook County (Figure 2). Possible breeding evidence was observed in 2.3% (107/4,736) of all surveyed blocks and 1.8% (43/2,337) of priority blocks (Figure 3; Table 1). Confirmed nesting was reported from 12 blocks in Carlton, Itasca, Lake, and St. Louis Counties. The confirmed nesting in Carlton County extended recent breeding observations southward beyond reports by Janssen (1987) and Hertzel and Janssen (1998). Over 100 years ago Roberts (1932) “found this woodpecker rather common in Carlton County,” including with “young that were nearly full grown.” Overall the species is most numerous in northern Cook, Lake, and St. Louis Counties and sparsely distributed in suitable coniferous habitat in many areas of northern and north-central Minnesota.

Tremblay et al. (2016), in their review of the Black-backed Woodpecker in North America, identified no known changes in the breeding range or population but did point out that it was formerly a common winter resident in southeastern Wisconsin. As for many rarer species that reside in the northern forested regions of Minnesota, coverage of these regions was sparse in the 19th century and well into the 20th. Combined observations from records of the Minnesota Ornithologists’ Union, the MBS, and the MNBBA suggest that the distribution of this species has not changed substantially over the past 150 years. Because the species has an affinity for naturally disturbed forests, recent fire suppression may have contributed to reduced populations in many areas. The woodpecker makes limited use of logged areas unless dead trees remain that have suitable wood-boring insect populations.

*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.

Black-backed Woodpeckers are primarily found in mature conifer-associated forests and especially those affected by forest fire, insects, windthrow, or beaver activity (Figure 4). During the Ontario breeding bird atlas, Cadman et al. (2007) found it in mature and old-growth conifer and mixed-wood forests and recently burned forests. Niemi (1978) found the species relatively common in virgin, burned jack pine forests in the Boundary Waters Canoe Area Wilderness two to four years after the Little Sioux Fire in northern Minnesota. It was relatively rare in the unburned forest surrounding these areas. Data gathered during the National Forest Bird (NFB) Monitoring Program found it significantly more common in black spruce–tamarack forests (Niemi et al. 2016). It has not been commonly recorded in the Red Lake Peatland area, which has extensive lowland black spruce–tamarack forests, perhaps due to the lack of fire or insect outbreaks (Niemi and Hanowski 1992; Bednar et al. 2016).

The importance of burned versus unburned forests to the Black-backed Woodpecker from a landscape perspective has been debated. For instance, Hutto (1995) suggested that the Black-backed Woodpecker in the western United States was restricted to early post-fire coniferous forests and that populations were maintained by patches of recently burned forests. In contrast, Tremblay et al. (2016) provided a counterargument based on a landscape model that predicted burned forests provided only short-term pulses in the population, while long-term stability in the population was more dependent on older, unburned forests. Additional research, especially long-term field data, will be required to better understand the landscape requirements of this species.

Partners in Flight estimated a North American population of 800,000 breeding birds and a Minnesota population of 4,000 individuals (Partners in Flight 2017). Canada, where a bulk of the species’ population resides, estimated a range of 500,000 to 5,000,000 adults (Environment Canada 2011). Population estimates for Minnesota by the MNBBA were unreliable because of its low population.

Breeding population trends for this species based on the federal Breeding Bird Survey (BBS) were unreliable for Minnesota. BBS routes were also unreliable for estimating trends for all the Canadian provinces, for Canada, and survey-wide. The mean number observed for all these regions was a fraction of 1 detection per route from 1966 to 2015 (Sauer et al. 2017). Despite these low numbers, Partners in Flight (Rosenberg et al. 2016; Partners in Flight 2017) estimated the North American population had increased by 73% since 1970. Environment Canada (2011) noted that a substantial part of the species’ population occurs in roadless areas not covered well by the BBS which implies that the population is underestimated.

Density estimates are relatively uncommon. Niemi (1978) estimated 3 pairs per 40 ha in a recently burned, virgin jack pine forest in the Boundary Waters Canoe Area Wilderness of northern Minnesota. Apfelbaum and Haney (1981) found no breeding pairs in a 6.25 ha area before a fire, and 2 pairs per 6.25 ha one year after a fire in the Boundary Waters Canoe Area Wilderness. Kendeigh (1947) reported 0.05 birds per ha in a spruce-fir forest during a spruce budworm outbreak in Ontario.

Mean densities in the Chippewa and Superior National Forests were 0.49 and 0.45 detections per 100-10 min unlimited distance point counts, respectively. In comparison, the most common woodpecker species in these forests, the Yellow-bellied Sapsucker, had a mean of 26 and 22 detections per 100-10 min unlimited distance point counts in the Chippewa and Superior National Forests, respectively (Niemi et al. 2016).

Overall populations in Minnesota forests are very low and difficult to detect but can be high locally in forests disturbed by fire, insects, wind, or other factors.

The Black-backed Woodpecker was assigned a moderately low score of 9/20 by Partners in Flight (Rosenberg et al. 2016), which suggests it is of minimal conservation concern in North America. It was also designated secure by Environment Canada (2011). The Minnesota Department of Natural Resources (2015) included it as a Species in Greatest Conservation Need due to concerns about habitat loss, habitat fragmentation, and the reduction of ecological processes that used to provide adequate habitat conditions for the species. The latter concern is primarily fire suppression, which minimizes the availability of burned forests

The Black-backed Woodpecker was identified as “climate threatened” by Langham et al. (2015) and the National Audubon Society (2015). Their models suggested a 75% decline in its current winter range and a likely extirpation from Minnesota by 2080. If climate change leads to increased forest fires or other disturbances, then the Black-backed Woodpecker may benefit from the creation of more suitable habitat. As noted above, the importance of burned areas for the Black-backed Woodpecker over the long-term are unclear.

The Black-backed Woodpecker is a unique species of the northern boreal forests of Minnesota. Its presence anytime of the year usually creates some excitement by the birding community and other wildlife observers. Its status, however, given climate change and a variety of unknown factors that may affects its population and distribution, renders its future as precarious in Minnesota.