Northern Prairie Wildlife Research Center
Breeding Range. (Fig. 6). Common in the Turtle Mountains; fairly common on the Northeastern Drift Plain and Missouri Coteau; fairly common locally on the Northwestern Drift Plain, particularly on the J. Clark Salyer, Upper Souris, and Des Lacs National Wildlife Refuges; uncommon elsewhere on the Northwestern Drift Plain, on the Southern Drift Plain, and in the northern portion of Agassiz Lake Plain Region (Pembina and Walsh Counties); rare, local, and probably irregular in other portions of the state--definite breeding record near McKenzie in Burleigh County and records of breeding pairs on Demicks Lake in McKenzie County and in Township T138N, R100W of Billings County.
During the early pioneering days, Horned Grebes apparently were more common on the Northeastern Drift Plain and in the northern portion of the Agassiz Lake Plain Region than they are at the present time. According to Williams (1926), this species bred in countless numbers on the big sloughs of the Bowesmont-Glasston area of Pembina County from 1882 until 1910 when the sloughs were drained. Job (1902) reported that during the summer of 1901, Horned Grebes were found everywhere on the prairie sloughs in the northeastern quarter of North Dakota, usually occurring as solitary pairs.
Breeding Habitat. The majority of the breeding pairs recorded were found on fresh to slightly brackish, seasonal, semipermanent, and permanent ponds and lakes containing expanses of open water, and ranging in size from 1/3 of an acre to several hundred acres or more; occasionally a few pairs were observed on moderately brackish and brackish semipermanent ponds and lakes. Horned Grebes are also characteristic of shallow river impoundments that are managed for waterfowl. Usually, extensive beds of submerged aquatic plants are present including such species as sago pondweed, claspingleaf pondweed, white watercrowfoot, common watermilfoil, and common bladderwort.
This species resembles the Red-necked Grebe in that breeding pairs are usually isolated from each other, occurring either as solitary pairs on the smaller ponds or as widely scattered pairs on the larger lakes. However, on June 16, 1961 in Ward County, five active nests were found on a 43-acre pond, including two nests that were only 220 feet apart (RES).
Nesting. Breeding season: Late May to mid-September; peak, early June to early August. Extreme egg dates (42 nests): May 26 [1967] in Divide County to July 21 [1960] in Stutsman County (RES). Extreme dates of dependent young (12 broods): June 12 [1927] in Burleigh County (N. Dak. Historical Museum record file - young collected) to September 13 [1962] in Stutsman County (RES).
The floating nests were usually situated over dense beds of submerged vegetation either on open water or under emergent marsh cover near open water. Water depths measured at 11 nest sites ranged from 6 to 48 inches and averaged 16 inches. Most nests were located within 100 feet of the shore. Materials used in construction of nests consisted almost entirely of matted submerged vegetation with a definite preference indicated for common watermilfoil whenever it was available.
Indicated clutch size (13 nests): 3 to 6 eggs; mean, 4.5 eggs.
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| Figure 6. Breeding Range of Horned Grebe. |
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U.S. Department of the Interior |
U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/birds/bbofnd/species/30.htm
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