US Fish & Wildlife Service


Date of this Version



Published in Prairie Naturalist 27(1 ): March 1995. Used by permission.


We monitored wood duck (Aix sponsa) population expansion into the Milk River Valley in north central Montana during 1975-1993. First -ever observations of wood ducks in isolated pairs or groups occurred on or near the Milk River in Blaine, Phillips, and Valley counties during 1975-1979. Broods seen east of Nelson Reservoir in 1975 and near Malta in 1980 were the first-ever verification of production in this area. Natural pioneering was supplemented with the transplanting of 35 first-year wood ducks near Dodson and at Bowdoin National Wildlife Refuge (NWR) in August 1980. Wood duck population expansion into tributaries of the Milk River occurred during 1985-1987, and at Bowdoin NWR during 1988-1990.