Northern Flicker

A regular breeding resident and migrant; a regular winter visitor in the southern half of the state. The Northern Flicker was abundant during the Minnesota Breeding Bird Atlas (MNBBA).

Widely distributed from central Alaska, across Canada, and south through the United States and portions of Central America. The species is absent from only some of the most arid regions of the Southwest. It is least abundant in the southeastern United States (Figure 1).

Assigned a Continental Concern Score of 9/20 by Partners in Flight.

Variable, but most northern populations are short-distance migrants that spend winters in the southern states.

Insects, primarily ants secured by foraging on the ground.

Primary cavity excavator; cavity located in snags 2 to 5 m above the ground; occasionally uses an existing nest cavity.

The Northern Flicker is a common breeding resident throughout Minnesota. It has been known by a variety of common names as biologists have separated or combined different races into full species. Depending on when the taxonomic decisions were made, Minnesota flickers have been known as Northern Flickers, Yellow-shafted Flickers, and Common Flickers. Birds that reside in Minnesota’s open woodlands have yellow tails, wings, and feather shafts. Farther west, these same features are red, thus the name Red-shafted Flickers. This difference, coupled with other plumage differences on the head and nape, led biologists to consider the two forms distinct species until the 1960s, when the combined species became known as the Common Flicker. The name Northern Flicker, originally another name for the Yellow-shafted Flicker, came into use again when a southern race, the Gilded Flicker, was separated into a full species.

Indeed, when Roberts wrote his account of the bird in 1932, he had two separate entries: one for the Northern Flicker, and one for the Red-shafted Flicker. In the early 1900s there were two specimens and a couple of sightings of the latter bird in Minnesota. Roberts’s examination of the specimens led him to conclude, however, that they were both hybrids between the Northern (i.e., Yellow-shafted) and Red-shafted species.

Roberts described the Northern Flicker as a common breeding resident throughout the state. Breeding evidence, including both confirmed (nests with eggs or young) and inferred nesting records (nest excavation, nests, or feeding young) was available from 7 counties stretching from Jackson County east to Goodhue County, and north through Ramsey, Hennepin, McLeod, and Meeker Counties in central Minnesota, and Marshall County in the far northwest. Although common during the breeding season, some of the most notable reports were of huge flights of birds seen during migration, particularly during the fall. Roberts wrote of a fall flight he witnessed in Itasca State Park in September 1921, when “for several days thereafter the ground was covered with flickers and robins too numerous even to estimate.” During his own lifetime, the most notable change in the flicker’s distribution and abundance was an increase in the number of birds that attempted to spend the winter in southern Minnesota.

Green and Janssen’s updated account of the flicker (then identified as the Common Flicker) in 1975 also described it as a numerous and widespread species throughout the state. The most significant change again was the increase in the number of wintering birds, with regular reports as far north as the cities of Duluth and Moorhead. Whether these birds were summer residents that lingered into early winter before migrating south or migrants from farther north was unknown.

By the time Janssen provided another updated account in 1987, the species’ common name had changed back to Northern Flicker. Although its summer status remained unchanged, there was at least 1 report of an individual that spent the entire winter in Minnesota in Pennington County. Because the number of reported sightings declined after mid-January, most winter observations now were thought to be lingering migrants. Janssen also identified 38 counties, covering all regions of the state, where flickers had been confirmed nesting since 1970. By 1998 Hertzel and Janssen added an additional 6 counties to the list.

Fieldwork conducted across the state by the Minnesota Biological Survey added further details on the species’ abundance and statewide distribution. As of 2016, surveyors have reported a total of 1,014 breeding season observations of the species. Records were available from nearly every county where survey work had been conducted (Minnesota Department of Natural Resources 2015).

During the MNBBA, observers reported a total of 4,468 Northern Flicker records from 55.8% (2,663/4,772) of the atlas blocks that were surveyed and from 72.4% (1,691/2,337) of the priority blocks. Breeding evidence was found in 325 atlas blocks (Figures 2 and 3; Table 1). The birds were reported from each of Minnesota’s 87 counties, and breeding was reported in 70 counties; 31 of the counties were additions to the list Hertzel and Janssen published in 1998. Eleven of the 17 counties where breeding was not confirmed were located south of the Minnesota River. The only region of the state where records were sparse was the intensively cultivated lands of the Red River valley, west of Glacial Lake Agassiz’s beach ridges.

The Northern Flicker is the most common member of the woodpecker family in Minnesota. During the MNBBA, nearly 1,200 more records were reported for the Northern Flicker than for the second most common woodpecker, the Yellow-bellied Sapsucker.

The predicted distribution map generated using MNBBA data predicted the flicker will be encountered statewide but will attain its highest breeding densities in the deciduous and mixed forests and woodlands of northern Minnesota (Figure 4). Although predicted to be least abundant in the extensively forested region of Lake and Cook Counties, the expansive Ham Lake fire of 2007 opened up the forest canopy so that in the years following the fire, the landscape should provide suitable habitat. On one hand it appears that the prediction model may underestimate the species abundance south of the burn area (Figure 2). On the other hand, the predicted distribution is nearly identical to that illustrated by the relative abundance map generated with BBS data (Figure 1).

Like that of other members of the woodpecker family, the overall distribution of the Northern Flicker has changed very little over the past 100 years within Minnesota and throughout North America. Local and regional changes in distribution and abundance usually reflect major habitat alterations. In the Great Plains, for example, the species has flourished in the riparian woodlands that have matured along major rivers since the early 1900s (Wiebe and Moore 2008).

*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.

Flickers inhabit a wide variety of woodland habitats, including forest edges, farm woodlots, shelterbelts, riparian forests, young successional forests, and savannas (Figure 5). The primary habitat requirements are a relatively open canopy, suitable nesting trees, and an open understory for foraging (Wiebe and Moore 2008). Nests are placed in dead snags or dead limbs of live trees. In northern forest regions, aspen trees are a favored nest tree since heartrot softens the interior and makes excavation easier (Wiebe 2001; Martin et al. 2004; Harestad and Keisker 1989).

In Minnesota’s northern forest region, flickers frequently are associated with edges created by recent clear-cuts. The clear-cut’s exposed ground provides ideal foraging habitat, while the adjacent forest stand provides nest trees (Danz et al. 2007).

Long-term monitoring of forest songbirds on four national forests in northern Minnesota and Wisconsin also documented Northern Flickers in a wide variety of habitats, from mature upland white pine and red pine stands to lowland hardwoods and black spruce/tamarack stands (Niemi et al. 2016). Statewide data collected during the MNBBA lend further support to the species wide tolerance of forest community types within 200 m of point counts where it was detected. Although the species demonstrates a strong preference for upland coniferous forests it is equally at home in a diversity of other vegetative communities that satisfy its requirements for an open canopy, suitable nest trees, and available foraging habitat (Figure 6).

Using data from the BBS, biologists have recently estimated the size of the Northern Flicker’s North American population to approximate 9.9 million birds (Rosenberg et al. 2016). Several years earlier, biologists estimated that Minnesota supported approximately 1.5% of the North American population (Partners in Flight Science Committee 2013). When that percentage is applied to the most recent North American estimate, the statewide estimate for Minnesota is nearly 150,000 breeding adults. Given the species statewide distribution and relative abundance, this estimate may be too low.

Although flickers are broadly distributed across Canada and the United States, they do not reach especially high breeding densities anywhere in their breeding range (Figure 1). In Minnesota, an average of 4 to 5 birds are observed on BBS survey routes each year; this is a little higher than the survey-wide average of 3 birds per route. Numbers are highest in several New England and eastern seaboard states. Connecticut has the highest annual average of 6 birds per route (Sauer et al. 2017).

Reported densities of breeding pairs are few and vary widely, ranging from a low of 1 pair per 111 ha to a high of 1 pair per 4 ha (Wiebe and Moore 2008). On Minnesota’s two national forests, observers detected an average of 5.47 flickers per 100 unlimited distance, 10 minute point counts on the Chippewa National Forest, and 9.47 on the Superior. This compares to an average of 26.08 Yellow-bellied Sapsuckers on the Chippewa and 22.17 sapsuckers on the Superior, the most common woodpecker on both national forests (Niemi et al. 2016).

Since the BBS began in 1966, the Northern Flicker’s population has demonstrated a significant average annual decline of 1.33% per year survey-wide, from southern Canada south to the Mexican border. This decline has abated somewhat since 2005 (Sauer et al. 2017). In Minnesota the decline is significant and steeper, averaging 2.51% per year (Figure 7). Although population declines have been observed throughout the species’ breeding range, they are most widely spread in the eastern and central United States. The species was originally identified as a Common Species in Steep Decline by Partners in Flight (Rich et al. 2004) but has since been removed from the list (Rosenberg et al. 2016).

A long-term forest bird monitoring program directed by Niemi and his colleagues from 1995 to 2016 documented a nonsignificant population trend for the flicker on both the Chippewa and Superior National Forests in northern Minnesota as well as a stable, combined regional trend (Figure 8). This suggests that the statewide decline detected by the BBS may be more concentrated in regions to the south and west of the Laurentian Mixed Forest Province. This is borne out by Figure 9 which illustrates that local populations are stable to increasing throughout portions of northern Minnesota but decreasing in central and southern regions.

Factors responsible for the species’ range-wide decline are not well understood. Wiebe and Moore (2008) have proposed three hypotheses: (1) competition for nesting cavities with European Starlings, who aggressively usurp nesting cavities from flickers; (2) a decline in suitable nest cavities due to habitat loss; and (3) pesticide use both in agricultural fields and urban/suburban neighborhoods where flickers forage.

Despite its declining population, the Northern Flicker remains a relatively common and widespread species. It has been assigned a moderate Continental Concern Score of 9/20 (Rosenberg et al. 2016). Although populations are experiencing a significant decline in Minnesota, at least in the densely forested landscapes of northern Minnesota, populations are stable. This could be attributed to sparse populations of starlings in the forests and strong forest management policies that emphasize the retention of snags. Indeed, as Figure 9 shows, flicker populations are stable to increasing in northern Minnesota but declining throughout the central and southern regions, where agricultural activity and suburban development are intense and where starling populations are dense and widespread.

Among the challenges Northern Flickers must contend with, climate change is not currently considered a major concern. The North American Bird Conservation Initiative (2010) rated the species as having a low vulnerability to climate change. As for many species, however, as our knowledge of the impacts of warming temperatures increases, potential impacts warrant reexamination. In the interim, the future of Minnesota’s most abundant woodpecker may well depend on insuring that sufficient dead and dying trees remain near open foraging areas where pesticide use is minimal.