Assessing the sensitivity of wetland bird communities to hydrologic change in the eastern Great Lakes region

Abstract

Uncertainty about the effects of ongoing natural and anthropogenic changes to Great Lakes ecosystems, such as managed stabilized water levels, coupled with widespread public interest regarding status of wetland birds prompted us to evaluate sensitivity of regional wetland birds to hydrologic changes. We reviewed published literature to determine preferred habitat of 30 wetland birds in the region, emphasizing vegetation required for foraging and nesting during the breeding season. Species were subsequently assigned to one of three risk categories based on association with vegetation types sensitive to water-level stabilization, as well as nesting height above water. Notably, of the bird species designated as low, moderate, and high risk, 25%, 33%, and 63%, respectively, have been regionally declining based on Bird Studies Canada’s Marsh Monitoring Program. This evaluation may be useful to regional biologists, planners, and managers concerned with predicting how particular species might be affected by future hydrologic changes in this and related systems.