Horicon Marsh National Wildlife Refuge

At over 32,000 acres in size, Horicon Marsh National Wildlife Refuge is the largest freshwater cattail marsh in the United States. The marsh provides habitat for endangered species and is a critical rest stop for thousands of migrating ducks and Canada geese. It is recognized as a Wetland of International Importance, as both Globally and State Important Bird Areas and is also a unit of the Ice Age Scientific Reserve.

Several hundred thousand Canada geese migrate between Hudson Bay and southern Illinois, stopping here briefly. In addition, over 223 species of birds also call the marsh home, including thousands of redhead ducks as well as deer, red fox, otters, muskrats, snapping turtles, and garter snakes. The marsh supports the largest blue heron nesting rookery in Wisconsin. Shorebirds, marsh birds, terns, raptors, and songbirds also use the marsh.

The northern two-thirds of Horicon Marsh is managed by the U.S. Fish & Wildlife Service as the 21,000 acre Horicon National Wildlife Refuge. The southern third of the marsh is managed by the Wisconsin Department of Natural Resources as Horicon Marsh State Wildlife Area. The National Wildlife Refuge System has over 545 such refuges across the country.

The marsh is a 14 mile long, shallow, peat-filled lake bed scoured out of limestone by glaciers over 70,000 years ago, surrounded by escarpments (hills).

The Horicon TernPike Auto Tour Route located on State Highway 49, just east of the city of Waupun, is open daily year-round, weather permitting. Three hiking trails are located here along with a floating boardwalk and bicycling and hiking access to the Wild Goose State Trail.

It is commonly asked when the peak of migration is at Horicon Marsh and that depends on which group or species of birds we are talking about. The best migration time to see the greatest variety of birds is from mid-April to mid-May and mid-September through October. However, there is no one time when you can see all the birds of the marsh. By the time one group of birds is at its peak, others may have already departed or might not yet have even arrived. Therefore, to see the greatest variety of birds it requires several trips throughout the season and throughout the year in order to get a true feel for the diversity and abundance of wildlife that is attracted to and supported by Horicon Marsh. Here's a month-by-month listing of the approximate times for various species.
Over the years, a total of 290 species of birds have been sighted at Horicon Marsh. Among them are many common wetland and upland birds and some of Wisconsin's rarest bird sightings. On a single day in spring it is not unusual to find up to 100 species of birds on Horicon Marsh alone!
Our visit was at the end of our summer drive around Lake Michigan and was the "off-season," but we still saw a number of waterfowl. Here are many photos of Horicon waterfowl.