Healthy Coastal Habitats: Cat for the Birds in Lake Michigan’s Green Bay
By Moira Herrington, Wisconsin Sea Grant
It’s for the birds is a phrase often used to disparage something. But there’s nothing to disparage about the “spine and fingers” stretching into Lake Michigan’s Green Bay. These form the anchor for a restoration project of a chain of barrier islands, known as the Cat Islands. The final restored chain will be the result of 30-plus years of planning with involvement from four Wisconsin Sea Grant outreach specialists and in partnership with the U.S. Army Corps of Engineers, Wisconsin Department of Natural Resources, Port of Green Bay/Brown County and the U.S. Fish and Wildlife Service.
The piping plover is endangered in Wisconsin. For the first time in 75 years, a piping plover pair has successfully nested in Green Bay in newly restored habitat that Wisconsin Sea Grant and partners have created.
The Cat Islands were completely washed away—after years of erosion and large spring storms—in the 1970s, leaving the mainland’s wetlands vulnerable to waves and bay-based storms, and compromising wildlife habitat. Now in the headlights are more than 1,400 acres of emergent wetlands and 272 acres of barrier islands. The islands are being constructed using dredged materials for the shipping channel of the bay.
“Shipping operations generally place channel and harbor dredged materials in confined disposal facilities, which are big-ticket items,” said Gene Clark, a Wisconsin Sea Grant coastal engineer. “The facilities can cost $30 million or more to build and many in the Great Lakes are nearing capacity because the material is left in the facility forever. The dredged materials that go into them—if clean and not contaminated—can be, alternatively, put to a sustainable re-use at construction sites, for beach nourishment or habitat creation or restoration. Habitat restoration is, in fact, precisely what’s going on in Green Bay through an ingeniously designed disposal facility.”
Water Quality Specialist Julia Noordyk also noted, “This project is a great educational opportunity and the hope is that restoration of these islands will help reestablish upland and shore habitat, and the wetlands behind the island barrier, to the benefit of fish, water fowl and shorebirds.”
In fact, the chain does hold out hope for an endangered 2-ounce bird called the piping plover. The delicate buff-colored bird with a black band encircling its neck is found on the Atlantic and Gulf coasts, as well as inland. It’s been scarce in the Great Lakes region, though, since human activity has compromised its habitat and ability to reproduce. Residential and commercial development limits nesting options. If there is too much activity around ground-based nests, the pair will abandon eggs. A 2007 survey found only six nesting pairs of piping plover in Wisconsin.
This summer, one pair nested on the emerging Green Bay islands and successfully fledged three chicks. Other birds are finding the slowly emerging islands a haven. Shorebirds—30 different types—have been spotted, including the red knot, which is classified as threatened under the federal Endangered Species Act. The rare-in-Wisconsin gull-like Forster’s tern has also bred in lower Green Bay for the first time in 20 years. In fact, there are four different tern species that have now been documented.
Now, the islands really are for the birds—and for a clearer shipping channel and protected mainland.