USGS Home
Contact USGS
Search USGS

In several bays there is not much boat traffic and large numbers of diving ducks are able to feed undisturbed. Baited sanctuary areas throughout the marshes increase the carrying capacity for dabbling ducks and Canada geese (Branta canadensis). Many redheads (Aythya americana) and canvasbacks (Aythya valisineria) are present during both spring and autumn in one section of the Detroit River near the mouth of the Canard River, which has limited boat traffic. Although marsh habitat appears to be fair quality, human disturbance and absence of suitable sanctuaries causes lower use by waterfowl than expected. Some dabblers use the area less during autumn because of power boat traffic. Although disturbance during autumn also affects diving ducks, they can rest on the open waters of Lake Erie during the times of peak disturbance on the bay. Dabbling duck habitat is of low quality, except in the Grand River marshes, where heavy hunting pressure and lack of suitable sanctuaries cause most of the dabbling ducks to leave shortly after opening day.