- Minnesota Breeding Bird Distribution
- Breeding Habitat
- Population Abundance
- Literature Cited
A regular, year-round resident, the Eastern Screech-Owl was a rare species during the Minnesota Breeding Bird Atlas (MNBBA).
The Eastern Screech-Owl is largely an inhabitant of the eastern deciduous forest from the Mississippi River east to the Atlantic Coast. In the Great Plains it is restricted to scattered woodlots and wooded riparian corridors bordering rivers and streams. Widely dispersed throughout its range, it is rarely present in high densities (Figure 1). In the southern Great Plains, the ranges of the Western Screech-Owl and Eastern Screech-Owl are either close to one another or actually overlap.
Assigned a Continental Concern Score of 10/20 by Partners in Flight.
A permanent resident. Some have suggested that northern populations may move south during the winter months, but this is likely a response to winter food shortages.
An efficient, opportunistic predator that consumes a wide array of invertebrates and small vertebrates. A nocturnal predator, daytime is largely spent roosting in cavities or perched in a tree in dense cover.
Cavity nester that uses natural cavities, abandoned woodpecker cavities, and artificial nest boxes.
When Roberts (1932) prepared his account of the Eastern Screech-Owl in Minnesota, he described it as a common resident that bred throughout the state. At the time, breeding records were available from five counties: Pipestone (brood out of nest and able to fly); Rice (brood of fledglings); Hennepin (nest); Grant (downy young out of nest); and Polk (nest). Roberts often made sweeping generalizations regarding a species’ distribution. In this case there were no records from north-central or northeastern Minnesota.
Indeed, in 1975 Green and Janssen reported that the species occurred throughout much of the state but, with the exception of a few observations, was “probably a rare resident from Roseau to Carlton counties.” And, other than a few records from southern St. Louis County, it “was absent from Cook, Lake, Koochiching, and Itasca counties.” Special note was made of the species’ decline in abundance since the 1960s.
A few years later, Janssen (1987) summarized the owl’s status as primarily restricted to the southern half of the state. Scattered records continued to be reported further north, including a breeding record in Otter Tail County, but the majority of records were from counties south of a line from the east metro region west to Lac qui Parle County. Since 1970, nesting had been confirmed in a total of 17 counties. Hertzel and Janssen (1998) would later add an additional six counties to that list, all from Wadena County south.
Although field biologists with the Minnesota Biological Survey have been conducting intensive bird surveys throughout the state since the late 1980s, nocturnal surveys for owls have not been a focus of their efforts. As a result, only two breeding season locations of the Eastern Screech-Owl have been documented by the survey, both located in southwestern Minnesota (Minnesota Department of Natural Resources 2016).
During the MNBBA, observers reported a total of 64 records of the Eastern Screech-Owl from 1.2% (58/4,743) of the surveyed atlas blocks and 1.2% (28/2,337) of the priority blocks. Breeding was confirmed in 12 blocks (Figures 2 and 3; Table 1). These birds were observed in 36 of Minnesota’s 87 counties (5 of the counties were included because blocks straddled county lines) and breeding was confirmed in 14 counties (3 blocks with confirmed nesting straddled two counties each: Stearns/Morrison, Hennepin/Dakota, and Mower/Olmstead). Seven of the counties were additions to the list published by Hertzel and Janssen (1998): Anoka, Houston, McLeod, Morrison, Mower, Pipestone, and Wabasha. The majority of records were located from the southern two-thirds of the state, from Lake Mille Lacs south to the Iowa border. A few scattered records from the northern regions were restricted largely to northwestern Minnesota. Breeding was most frequently reported from the southern portion of Minnesota’s Eastern Broadleaf Forest Province.
Overall, it seems that the Eastern Screech-owl’s distribution in the state has changed little during the past 100 years. It remains unclear, however, just how common they were in the northwestern and north-central regions in earlier times. Today they are quite rare in these regions; only five MNBBA records were documented north of southern Aitkin County.
The owl’s abundance, however, appears to have declined significantly. Roberts (1932) described it as “the commonest member of its family in Minnesota. Wherever there is a growth of trees, even if only a small grove out on the prairie, it may be expected to make its home.” Today, it is a rare sight to come across the bird. Areas where its distinctive nighttime tremolo was commonly heard are now silent. During the MNBBA, the screech-owl was far outnumbered by the Barred Owl, the Great Horned Owl, and the Northern Saw-whet Owl. Even the Great Gray Owl, which was not known as a nesting species in the early 1900s, outnumbered the Eastern Screech-Owl with 83 reports.
Elsewhere in North America, the species has actually expanded its breeding range, especially in Canada. Ritchison and his colleagues noted recent expansions to the northwest across the Canadian Prairie Provinces, north in Manitoba, and east in Ontario. They suggested that urbanization, which is often accompanied by more tree plantings, and warming temperatures may be facilitating these changes (Ritchison et al. 2017). Atlases conducted in other states and provinces showed mixed results. Ontario, for example, documented a significant increase in records between its first and second atlases but also developed a targeted survey for screech-owls and extended its period for acceptable observations during the second atlas (Cadman et al. 2007). Iowa, on the other hand, reported a significant decline in observations between atlases (Iowa Ornithologists’ Union 2017). Michigan witnessed little change but did note a slight retraction on the northern edge of the species’ breeding range in the state (Chartier et al. 2013). In his comprehensive review of Wisconsin birds, Robbins (1991) noted that the northern edge of the species’ range had receded since the 1930s and 1940s in the far northern reaches of the state and in the central regions in the 1960s and 1970s. Given that cold winter weather can be a factor that limits the Eastern Screech-Owl’s northern distribution, Cutright and his colleagues (2006) suggested that the species’ presence in northern Wisconsin may vacillate in response to “mini-climatic” changes over long periods of time.
*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.