Relationships between abundances of breeding ducks and attributes of Canadian prairie wetlands

Abstract

Understanding how animals respond to changing habitat conditions can improve predictions about effects of environmental change and also inform conservation planning. We examined relationships between abundances of 5 common dabbling duck species breeding in the Canadian Prairie Pothole Region and basic wetland metrics. Pond area was a well‐supported predictor of duck abundance at the local scale of pond. Relationships for all 5 species varied with their respective regional duck and pond densities. In regions where duck densities were high, there were more ducks per pond; conversely, there were fewer ducks per pond in regions where pond densities were high, indicating that mechanisms influencing local habitat use were, in part, mediated by processes occurring at larger spatial scales. Although models explained small amounts of variation of duck abundance on a per pond basis, these models explained more variation when results were aggregated to the level of survey segment, indicating reasonable performance of models for estimating duck abundance over specific areas with known pond areas. Our results also indicated that the greatest increase in duck abundance with increasing pond size occurs at the low end of the range of pond sizes. It is relatively small wetlands that face the greatest threat of loss and degradation on the prairies; therefore, protection and conservation efforts need to focus on these wetlands if the objective is to increase or maintain populations of the duck species studied. © 2017 The Wildlife Society.

Waterfowl distribution and productivity in the Prairie Pothole Region of Canada: tools for conservation planning

“…Duck pair numbers demonstrated a positive asymptotic increase with wetland area and count such that smaller basins held higher numbers of duck pairs per unit wetland area. This is likely a reflection of greater duck response to smaller wetlands observed at the basin scale (Cowardin et al 1995, Bartzen et al 2017) and may reflect greater opportunity for pair isolation and more food resources per unit area than found on larger basins (Dzubin 1969 b , Armstrong and Nudds 1985). More subtle variation in duck abundance was explained by latitude and land cover (cropland, grassland) likely in response to interacting influences on wetland productivity (e.g., nutrient inputs from cropland; Euliss and Mushet 1996, Hann and Goldsborough 1997) and hydrology (e.g., reduced runoff into wetlands in grasslands; Van der Kamp et al 2003).…”

Integrating dynamic processes into waterfowl conservation prioritization tools

“…These ponds receive most of their water as spring snowmelt running over frozen ground (Hayashi et al., 2016) and thus are available earlier in the spring than their deeper semipermanent counterparts. Dabbling duck pairs feed along the edges of these ponds, concealing themselves from predators and conspecifics (Bartzen et al., 2017; Kantrud & Stewart, 1977; Reynolds et al., 2006). Many of the temporary ponds used by dabbling duck pairs settling in the PPR are dry in the late summer (July–August) by the time waterfowl hens are raising broods (Johnson et al., 2010).…”

“…It is widely accepted that densely ponded areas attract the highest number of pairs. At more local extents, small, seasonal (sensu Stewart & Kantrud, 1971) wetlands tend to provide the best habitat for breeding dabblers (Bartzen et al., 2017; Cowardin et al., 1995; Fields, 2011; Reynolds et al., 2006). These ponds receive most of their water as spring snowmelt running over frozen ground (Hayashi et al., 2016) and thus are available earlier in the spring than their deeper semipermanent counterparts.…”

Multi‐level habitat selection of boreal breeding mallards

“…Wetlands are ideal habitat for breeding ducks (Kantrud and Stewart 1977, Cowardin and Golet 1995, Beatty et al 2014 a , Bartzen et al 2017, Kemink et al 2021). In our study, we considered 5 different wetland types including marsh, graminoid fens, shrub swamps, swamps, and treed peatlands (Table 1).…”