Date of this Version
The Prairie Naturalist, Volume 39, No.1, March 2007, pp 1-12
We radiotracked 308 mallard (Anas platyrhynchos) broods from hatching until 30 days of age Oij 15 study areas located throughout the Canadian Prairie Parklands to examine patterns of variation in movement frequency and distance. Broods moved an average of 350 m from nests to first wetlands (SO = 390), with 94% of broods moving less than I km. After leaving the nest, broods had a 23% probability of moving to a new wetland each day, but movement probability was a complex function of study area, hatch date, and ducking age, with younger and earlier-hatched broods exhibiting greater movement rates than older and later-hatched broods. Later-hatched broods moved farther than earlierhatched broods and movement distance also varied among study areas. Local wetland characteristics explained some of the among-site variation in movement rates and distances, with movement probability being most strongly correlated with average size of semipermanent wetlands and movement distance being most strongly correlated with total acreage of seasonal wetlands. After 30 days, broods were located an average of 760 m (SO = 610) from their nests, with 95% of all surviving broods located less than 2 km from their nests. Our data illustrated the need for suitable brood-rearing wetlands within a reasonable distance (e.g., < 0.5 km) of waterfowl nesting cover.