U.S. Fish & Wildlife Service logo A Unit of the National Wildlife Refuge System
Banner graphic displaying the Fish & Wildlife Service logo and National Wildlife Refuge System tagline

National Wildlife Refuge

redhead duck on water
W4279 Headquarters Road
Mayville, WI   53050
E-mail: horicon@fws.gov
Phone Number: 920-387-2658
Visit the Refuge's Web Site:
The refuge supports the largest number of nesting redhead ducks in the eastern United States.
Gray horizontal line
Horicon National Wildlife Refuge

Over 21,000 acres in size, Horicon National Wildlife Refuge is located on the west branch of the Rock River in southeastern Wisconsin and encompasses the northern two-thirds of Horicon Marsh.

Horicon Marsh is a shallow, peat-filled lakebed gouged out by the Wisconsin Glacier about 12,000 thousand years ago. The headwaters of the Rock River, Horicon Marsh is 14 miles long and three-to-five miles wide. Branches of the Rock River, small and intermittent streams, and groundwater springs provide the water resources for the marsh. At 32,000 acres in size, it is the largest freshwater cattail marsh in the United States.

In 1990, Horicon Marsh was designated a "Wetland of International Importance" by the Ramsar Convention. It has also been designated as "Globally and State Important Bird Areas" by the American Bird Conservancy and a unit of the Ice Age National Scientific Reserve.

Getting There . . .
To reach the refuge office/visitor center from Waupun, go 7 miles east on State Highway 49 and 3.5 miles south on County Road Z. From Milwaukee, take 41 north to the Brownsville exit, go west on Highway 49 and 3.5 miles south on County Road Z. From Madison, take 151 north to Highway 49, go east to County Road Z, go south 3.5 miles. From Fond du Lac, take 151 south to Highway 49, go east to County Z, go south 3.5 miles. We strongly suggest that you consult an atlas or Dodge County map when using these directions.

Get Google map and directions to this refuge/WMD from a specified address:

Your full starting address AND town and state OR zip code

Google Maps opens in a new window

NOTE: When using this feature, you will be leaving the U.S. Fish & Wildlife Service domain. We do not control the content or policies of the site you are about to visit. You should always check site policies before providing personal information or reusing content.

These driving directions are provided as a general guide only. No representation is made or warranty given as to their content, road conditions or route usability or expeditiousness. User assumes all risk of use.

horizontal line

Wildlife and Habitat

Major land types identified on the refuge include wetland (about 17,000 acres), of which the majority is classified as deep, freshwater marsh, and upland (about 4,000 acres), including grassland habitat.

Learn More>>

Horicon Marsh is a shallow, peat-filled lake bed scoured out by the Green Bay lobe of the massive Wisconsin glacier. The glacier entered this area about 70,000 years ago and receded about 12,000 years ago, leaving behind a long depression 14 miles long and three-to-five miles wide.

Learn More>>

Horicon NWR now featured on video DVD


Photograph of grizzly bear on DVD cover. Experience eight National Wildlife Refuges from Alaska to the Caribbean on this new two hour DVD.

See wildlife up close and personal  from grizzly bear and whooping cranes to red wolves and bald eagles. For more information, click on the photograph of the DVD cover.

Recreation and Education Opportunities
Environmental Education
Wildlife Observation
Learn More >>

Management Activities
Although the refuge may look pristine and untouched by human hands, staff must actively manage the refuge to benefit a diversity of wildlife for your enjoyment. Biological management activities include aggressive water level management, restoring upland habitat, monitoring waterfowl populations, providing artificial nesting structures, controlling invasive exotic species, and coordinating research studies.

Manipulating water depth is the most vital management tool used to benefit waterfowl and shorebirds. Success in establishing and maintaining productive aquatic vegetative communities is often directly related to controlling nuisance carp and inflowing and outflowing waters.

Various impoundments have been subdivided from the main pool of the marsh using a system of dikes. The impoundments are interconnected via water control structures like stop logs and pump stations. Water depth in these impoundments is managed on seasonal, annual, and multiple-year cycles to create wetland plant communities that meet the seasonal needs of wildlife.

Moist soil units are established via drawdowns in spring to encourage the growth of plants such as smartweed and millet. When reflooded in the fall, these units attract and provide food for fall migrants. During drawdowns, nutrients are released and the marsh bottom hardens. This drying process results in rejuvenation of the marsh, and, when reflooded, it thrives with animal life and aquatic vegetation essential to sustain marsh wildlife.