BREEDING BIOLOGY OF GREATER SANDHILL CRANES ON THE ROSEAU RIVERWILDLIFE MANAGEMENT AREA, MINNESOTA

The breeding biology of greater sandhill cranes (Grus canadensis tabida) on the Roseau River Wildlife Management Area in northwestern Minnesota wa.'I studied from April 1989 to October 1990. A minimum of 0.25 breeding pair per km of wetland and upland nested on the study area. Except for distances to nearest shrub from nest and random sites (P = 0.047), there were DO significant differences among mean habitat values or distributions of variables measured at nest and random sites (P > 0.05). Mean clutch size was 1.88 ± 0.33 (SD) eggs for 17 clutches in 1989 and 1990. In 1990, estimated hatch dates for 13 clutches ranged from 21 May to 12 June (x = 30 May ± 6.6 days [SD]), apparent egg hatching success was 69.2% (n = 26), and apparent and Mayfield corrected nest success were 73.3% (n = IS) and 53.8% (n = 14), respectively. Key Wordr: greater sandhill cranes, Orus canadensis tabida, Minnesota, nesting habitat preference, Roseau River Wildlife