The nearshore waters, shoreline and coastal uplands are the Great Lakes’ most ecologically diverse and biologically productive systems. They are also among the most heavily used by people and the most expensive to protect.
Dynamic physical processes can change where these habitats form and persist over millennia — or overnight when powerful storms blow through.
Wind and water transport sediment from place to place, causing dunes and wetlands to change in size and location; ice cleaves chunks of beach in the winter; lake levels fluctuate and coastal plants adapt to cycles of inundation and submergence.
By interrupting these processes and converting coastal habitats, people have altered this system. Many actions compromised both the diversity of life and the health of the system itself. Habitat losses have been staggering.
Wetlands play many vital roles, but they have been all but eliminated in some areas of the Great Lakes. More than 70 percent of Green Bay’s historic wetland habitat has been lost, while 95 percent of Lake Erie’s wetlands are gone.
The remnant coastal areas are often disconnected, making it hard for species to migrate or move. Pollution and nutrient runoff have reduced air and water quality. Invasive species have drastically changed nutrient flow and species interactions, to the detriment of many native and commercially important fish, including lake trout, perch and walleye.
As in other major system types, the Great Lakes Project is working to improve coastal sites and find ways to rehabilitate large-scale processes that support the reestablishment of former coastal habitats by:
Along the shores of the Great Lakes, all of the issues—economics, biodiversity, agricultural practices, industrial needs, invasive species—relate to and affect the others. Solutions must address these various facets and meet multiple objectives that rebuild and sustain healthy coasts.October 30, 2012