Habitat use of breeding diving ducks is not well-documented. I studied nesting and brood-rearing female redheads (Aythya americana) in southwestern Manitoba during 1994 and 1995 to document habitat use and associations between wetland characteristics and reproductive success. Most females nested in small, semi-permanent wetlands and were successful in wetlands with large bands of emergent cover. Success was associated with water depth at the nest and distance between the nest and dry land. Brood-rearing females switched from smaller wetlands used for nesting to larger, semi-permanent wetlands. Successful females selected appropriate habitat whereas unsuccessful females showed no preferences. These results support a landscape approach to wetland management and emphasize the need for plans that reduce impact to wetland margins.