When submitting eBird observations at Horicon National Wildlife Refuge, it is most helpful to start a new checklist for each hotspot within the refuge. Use the general hotspot when you have a checklist that includes multiple locations or if no other hotspot or personal location is appropriate for your sightings.

If you carefully keep your bird records by county, be sure to use the specific hotspots at Horicon Marsh so that the birds will be assigned to the proper county. The Fond du Lac-Dodge county line is on WI-49 where it crosses the refuge. A small portion of the refuge is north of WI-49 in Fond du Lac County. Most of the refuge is in Dodge County.

Horicon Marsh is one of the largest freshwater marshes in the United States and is a critical rest stop for thousands of migrating ducks and Canada geese. The U.S. Fish and Wildlife Service manages the northern two-thirds as the 22,000-acre Horicon National Wildlife Refuge. The southern third of the marsh, 11,000 acres, is managed by the Wisconsin Department of Natural Resources as the Horicon Marsh State Wildlife Area. Three visitor centers numerous trails and other outdoor facilities are available. 

While the marsh is primarily managed as a waterfowl area it hosts a variety of other birds. This marsh is perhaps best known for the spring and fall migration of Canada Geese which often number more than 200,000 birds. Over the years, more than 300 species have been sighted here and this marsh regularly attracts some of Wisconsin's rarest birds. 

Being a National Wildlife Refuge, public access is limited in this portion of the marsh to protect the wildlife for which it has been established. Most of the state area is open to the public. One of the best ways to explore this area is by canoe or shallow draft boat. Please be aware of designated restricted use and closed areas. For more information, contact the state or federal headquarters.