Habitat associations of breeding mallards and Canada geese in southern Ontario, Canada

Abstract

ABSTRACTUnderstanding habitat associations of breeding mallards (Anas platyrhynchos) and Canada geese (Branta canadensis maxima) in the eastern US and Canada is important for conservation planning, yet studies at spatial scales useful to conservation planners have mostly occurred in the midcontinent prairie pothole region (PPR). Our broad objective was to determine whether breeding pairs were associated with similar habitat types in an eastern ecozone, the mixed woodland plain of southern Ontario, Canada, as they are in the PPR, despite substantial differences in relative habitat availability and land use practices. We used helicopter surveys and remote sensing to investigate habitat associations at landscape (25 km2) and local (500 m wetland buffer [79 ha]) scales during the 2008 and 2009 breeding seasons. At both spatial scales, mallard indicated breeding pairs (IBP) were positively associated with the abundance or area of temporary open water and emergent (seasonal or semipermanent) wetland types, similar to the PPR. However, against expectations, we did not detect an effect of grassland area. Canada goose IBP were most strongly associated with total wetland abundance, and not specifically with emergent and permanent open‐water wetlands as expected. At the local scale, goose IBP presence was positively associated with riverine wetland area. Unlike the PPR, our study area contained a high proportion of forested and riverine wetlands; however, with the exception of the riverine wetland–Canada goose association noted above, we did not detect a disproportionate influence of these wetland types on mallards or geese. © 2015 The Wildlife Society.