Home range and movements of postfledging American black ducks in eastern Maine

We monitored the movements of 97 female and 15 male juvenile American black ducks (Anas rubripes) in the vicinity of Moosehorn National Wildlife Refuge in eastern Maine and southwestern New Brunswick from September through mid- December, 1985-1987.. Movements were described by estimating home ranges and radial movements from the primary roost marsh. Overall home range sizes averaged 4987 ha (range 54 - 28 070 ha), and maximum distances moved from the roost averaged 9.9 km (range 0.9-42.8 km). Home ranges were linear (linearity index 2.8), and home range area and distance of movements from the roost both increased monthly. Ducks that used >15 % riverine habitat had larger home ranges and moved greater distances from the roost than ducks using