The Role of Waterfowl

The lower Great Lakes (“LGL”: Lakes Erie, Ontario, and St. Clair, plus their associated connecting rivers) provide extensive and diverse habitat for migratory waterfowl in eastern North America. The region serves as a crossroad between the Mississippi and Atlantic flyways, with an estimated 12.8 and 7 million waterfowl passing through the Great Lakes each autumn and spring, respectively. In addition, approximately 1 million waterfowl remain on the LGL throughout winter in areas that remain relatively ice-free (e.g., Lake Ontario, as well as the Niagara, Detroit, and St. Clair rivers). The 29 species of waterfowl that inhabit the LGL are a diverse group that occur in nearly all types of aquatic systems. Omnivorous and herbivorous dabbling ducks, bay ducks (e.g., lesser scaup), geese, and swans occupy both coastal wetland and open lacustrine systems, whereas sea ducks (e.g., longtailed ducks) range from omnivorous to nearly exclusively carnivorous and forage primarily in open lacustrine areas from 1 to 30 meters deep. Millions of waterfowl migrate within North America and have substantial energy requirements associated with flight and ovulation. These nutritional requirements and associated rates of consumption by waterfowl can cause strong top-down trophic influences in terrestrial and aquatic systems. Because waterfowl are abundant and ubiquitous in nearshore regions of the LGL (aquatic and terrestrial) and other lakes in North America it is vital that foraging requirements (type, timing, and amount) and potential to influence trophic cascades be considered in aquatic food webs. Herein, we summarize knowledge The Role of Waterfowl in Lower Great Lakes Aquatic Food Webs