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Platte River Status: A common migrant and uncommon nesting species throughout the study area. Occurrence dates at the Mormon Island Crane Meadows, Hall County, extend from 30 April to 28 September. Tout (1947) speculated that sora nested in Lincoln County, although he had no June records. Rosche (1979) recorded sora in the lower North Platte River Valley during 23 April to 3 October.

Breeding Range: Our records suggest that sora is an uncommon and locally distributed nesting species in the Platte River Valley and on the Eastern Plain. Birds in the latter area primarily occur in the Rainwater Basin area. Sora is probably a locally uncommon nesting species in the Sandhills, although we have no records from that area.

Breeding Population: The population was estimated at 1,080 breeding pairs in 1979-1980.

Habitat: We found a mean nesting density of 10.5 pairs per km² in prairie wetlands. Most sora encountered in the study area were associated with dense emergent vegetation at the periphery of wetlands or in wet sedge meadows within the river channel. Faanes (1982) reported that most sora nesting pairs on a central North Dakota study area were associated with the dense emergent vegetation of semipermanent and permanent wetlands.

Effect of Habitat Alteration: Wetland loss through drainage for expanded agricultural production, and wooded vegetation encroachment of wet meadows has produced a negative impact on this species within the study area.

Nesting Data: We have located 2 nests or broods in sedge meadows at Mormon island including a downy chick on 10 June 1980, and a nest on 7 June 1984. Peak nesting activity in North Dakota occurs from early June to late July (Stewart 1975).