Fall and Winter Movements of Black and Mallard Ducks

Abstract

This paper summarizes the results of a study of fluctuations in fall and winter populations of black ducks (Anas rubripes) and mallard ducks (A. platyrhynchos) in central Ohio. The primary objectives were to estimate the duration of stopover of individual birds, and to determine if there was any correlation between local weather conditions and the departure of birds from the study area. Duration of stopover was estimated by trapping and color marking birds; the marked individuals were censused daily until all had departed from the study area. The total population was also censused daily, and weather conditions for those periods when the population decreased in size were examined for any weather factor or factors that might be consistently associated with departures. This paper is a contribution from the Ohio Cooperative Wildlife Research Unit and the Ohio State University Ornithology Laboratory: U.S. Fish and Wildlife Service, Ohio Division of Wildlife, Wildlife Management Institute, and The Ohio State University cooperating. I am grateful to Eugene H. Dustman and Loren S. Putnam for advice and encouragement throughout the course of the study. Information on the freezeup of the Lake Erie marshes was provided by Robert Donohoe.