by Tina Yerkes, Ph.D.
The Great Lakes contain 20 percent of the world’s fresh water, sustain an economy for 30 million people, and support millions of waterfowl throughout their annual cycle. This massive watershed drains 201,000 square miles and has over 10,000 miles of shoreline, which is more than the Atlantic and Pacific coasts combined.
Composed of six interconnected lakes, the Great Lakes are important for drinking water, sport and commercial fishing, waterfowl hunting, and other recreational activities. Some of the oldest hunting clubs in the United States and Canada are found along the shores of the Great Lakes, where waterfowlers still pursue mallards, black ducks, canvasbacks, and lesser scaup.
Conserving the region’s waterfowl habitat is wrought with challenges, including invasive species, expanding human populations, continued loss and degradation of habitat, and the effects of climate change. Nonnative species, such as the zebra mussel and purple loosestrife, are disrupting food webs and causing billions of dollars in damage to infrastructure and fisheries.
Birds that eat zebra mussels, which are filter feeders, ingest heavy metals and other toxins. Phragmites (common reed) and purple loosestrife displace native plants that provide nesting cover and food for waterfowl and other wetland species. Biologists have documented at least 185 invasive species in the Great Lakes system, and a new one is introduced every month.