Northern Prairie Wildlife Research Center
Breeding Range. (Fig. 85). Fairly common locally on the Northwestern Drift Plain and Missouri Coteau; uncommon and local elsewhere in the state.
Breeding populations often fluctuate greatly from year to year and appear to be related to cyclic variations in numbers of field mice (Microtus sp.). When mouse populations are high, scattered pairs of Short-eared Owls ordinarily are present. When mouse populations are low, this species is rare or absent. The fluctuations in Short-eared Owl populations in the state were first noted during 1925-1932 in Berlin and Harwood Townships of Cass County (Monson 1934).
Apparently, breeding Short-eared Owls were more generally distributed and more numerous during former years. In 1873, this species was reported as the most common of the owls along the expedition route from Fort Rice westward to the Montana line (Allen 1874). During August 20-26, 1874, considerable numbers were found along the Little Missouri River and on the headwaters of the Heart and Knife rivers (Grinnell 1875). Judd (1917) reported that it was a common summer resident within 40 miles of Cando in Towner County during 1890-1896. Bent (1901) found that the Marsh Hawk and Short-eared Owl were the characteristic breeding raptors in 1901 on the open prairies in the Devils Lake area, along the Sheyenne River to the south, and in Nelson and Steele Counties. The Short-eared Owl was considered to be a "tolerably common" breeding species in northeastern McKenzie County during 1912-1926 (Larson 1928). Williams (1926) reports that it was a very common summer resident within 20 miles of Grafton in Walsh County.
The marked reductions in breeding populations undoubtedly have been due to the widespread destruction of extensive tracts of native prairie by agricultural development.
Breeding Habitat. Short-eared Owls are characteristic inhabitants of various types of open habitat, including expanses of native prairie, swales and wet-meadow zones of wetlands, hayfields, retired cropland, and fallow stubble fields.
Nesting. Breeding season: Early April to late August; peak, late April to mid-July. Extreme egg dates (26 nests): April 4 [1963] in Stutsman County (K. D. Bayha and D. L. Trauger) to August 1 [1969] in Stutsman County (L. M. Kirsch). Extreme nestling dates (9 nests): June 7 [1915] in Richland County (H. H. Sheldon) to July 17 [1913] in Ward County (V. Bailey). Extreme dates of dependent young out of the nest (5 records): July 10 [1912] in Ramsey County (F. M. Bailey) to July 30 [1963] in Stutsman County(RES).
Nests are situated on the ground, usually in habitats with fairly dense herbaceous cover. These include native prairie, wet-meadow zones of wetlands, hayfields, retired cropland, and stubble fields.
Indicated clutch size (19 nests): 5 to 10 eggs; mean, 6.4 eggs. According to Rolfe (1897), the full clutch ranges from five to seven eggs; Mr. Rolfe collected seven sets of eggs in the Minnewaukan area of Benson County in 1897.
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| Figure 85. Breeding Range of Short-eared Owl. |
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U.S. Department of the Interior |
U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/birds/bbofnd/species/3670.htm
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