Northern Prairie Wildlife Research Center
Breeding Range. (Fig.14). Distribution of known nesting colonies and records of adults during the breeding season indicate that the Black-crowned Night Heron is a locally common breeding species throughout the Prairie Pothole Region. A few records also have been reported from the Coteau Slope and Little Missouri Slope. These include one large colony in northern Emmons County and observations of adults during the breeding season at other locations in Emmons County and in Burleigh, McLean, and Billings Counties.
Formerly, this species was found breeding in the Agassiz Lake Plain Region; Williams (1926) discovered a small colony near Minto in Walsh County, and adults were reported during the breeding season in southeastern Richland County (Bailey 1916a).
High estimated breeding populations recorded for selected representative breeding colonies are indicated as follows:
1,000 nests on J. Clark Salyer National Wildlife Refuge, McHenry County, on June 14, 1960 (R. Johnson).Breeding Habitat. Two distinct types of nesting habitat are commonly utilized in North Dakota. These are groves of small or medium-sized trees located in areas containing extensive wetlands, and large marshes, usually dominated by phragmites or bulrushes, that occur in natural lake basins or shallow river impoundments. In the marsh colonies, Black-crowned Night Herons are often associated with large numbers of breeding Franklin's Gulls. Adults from the nesting colonies may range out for several miles in order to reach various types of wetlands that contain suitable food organisms such as fish and amphibians.1,000 adults, 16 miles southwest of Kenmare in 1949 (R.T. and A.M. Gammell).
400 pairs on Long Lake, Burleigh County, in 1943 (bird record file of Long Lake National Wildlife Refuge).
250-300 pairs at Beaver Lake, Burke County, in 1974 (W. E. Steffin).
250 adults at Lake Nettie, McLean County, in 1961 (D. C. McGlauchlin).
100 pairs at Smishek Lake, Burke County, during 1964-65 (G. James).
100 pairs at Kraft Slough, Sargent County, during June 1974 (G. L. Krapu).
50-60 pairs at Audubon National Wildlife Refuge, McLean County, in 1974 (D. C. McGlauchlin).
50 nests at Sweetwater Lake, Ramsey County, on May 31, 1896 (E. S. Bryant).
50 nests at Jamestown, Stutsman County, on May 31, 1925 (O. A. Stevens).
30 nests at Lake Alice (Lac aux Mortes), Ramsey County, on June 16, 1892 (E. T. Judd).
Nesting. Probable breeding season: Early May to early August. A large colony, apparently engaged in nesting activities, was recorded on May 9 [1967] at Kraft Slough in Sargent County (RES). Extreme egg dates (hundreds of nests): May 19 [1900] in Ramsey County (A. D. Doerge) to June 29 [1960] in McHenry County (R. Johnson). Many nests containing young were observed on June 29 [1960] in McHenry County (R. Johnson).
Indicated clutch size (13 nests): 3 to 6 eggs; mean, 4.7 eggs.
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| Figure 14. Breeding Range of Black-crowned Night Heron. |
Young Black-crowned Night Heron. |
 Adult Black-crowned Night Heron in breeding |
U.S. Department of the Interior |
U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/birds/bbofnd/species/2020.htm
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