Wetland ecosystems and their maintenance (particularly the beaver pond complexes) are key to the waterfowl resource in this landscape. The most significant feature of the Shield ecosystem is that it is driven by a combination of repeated natural and human induced, cataclysmic, cyclic disturbances caused by fire, insect outbreak, wind damage or forestry activities. Historic large-scale natural disturbances such as fire and disease have provided the conditions necessary for the establishment and regeneration of shade intolerant species such as poplar and birch which are crucial food supplies to sustain beaver populations and in turn create wetland habitats.
Natural fire disturbances within the riparian zones throughout the 1920s, 30s and early 40s combined with recovery of beaver populations from over trapping caused a rapid expansion of beavers and hence wetland habitats that continue today. Unfortunately provincial fire suppression policies changed to aggressively suppress fire disturbance within the landscape partly in response to increasing human population. Concurrently forest policies and management practices have “protected” the riparian areas from virtually all forest harvesting disturbances. In much of the Shield area, a wide buffer must be left along all riparian areas to address soil erosion and fisheries values issues. These two factors combined with silvicultural activities that discourage aspen have created riparian habitat conditions that promote shade tolerant trees and severely limit tree species necessary for beaver colonies to sustain themselves.
This landscape functions primarily as breeding habitat for waterfowl, and contributes significantly to the GLSL waterfowl breeding population. More than half of the breeding population consists of mallard and wood duck with a significant portion of the world’s hooded mergansers also being produced in this landscape. Other significant breeding species include black duck, ring-necked duck, common goldeneye, Canada geese, and common and red-breasted mergansers. Breeding waterfowl densities vary greatly across the region primarily due to variations in relative fertility and wetland density found throughout the Shield.
The most threatening impact on the waterfowl resource throughout this landscape are the current fire suppression and forest management policies/guidelines which precludes disturbance in the riparian zone over large areas of the shield. In fact, suppression of forest fires has resulted in an overall decrease of disturbance by fifteen fold (Donnely and Harington 1978). Should these policies continue, beaver populations will decline resulting in a significant reduction in wetland habitats and breeding waterfowl capabilities throughout this landscape. Increased cottage development, hydroelectric, mining impacts and transportation corridors also present significant threat to the aquatic ecosystems.
- Maintain and average of 3 breeding waterfowl pairs/km2.
- Maintain a disturbance regime which mimics historic natural disturbance frequencies in riparian areas in order to create and maintain a mosaic of wetland and upland habitats necessary to sustain the waterfowl goal.