The area of Hamden Slough Refuge is known for its complex of prairie pothole wetlands, marshes and shallow lakes. Many historical accounts of the first settlers described the abundance of waterfowl on refuge waters. “Game was very plentiful, especially ducks, geese and prairie chickens. It was no trouble to keep our families in meat, as all we had to do was to look out on the lake in the morning and see where the ducks were…” (Wilcox 1907). Today, waterfowl numbers have rebounded since the restoration of numerous wetlands on the refuge. Common breeders include the mallard, blue-winged teal, canvasback and trumpeter swan; while all major waterfowl species are observed during migration.

The greater prairie chicken has long been a relic of the Minnesota tallgrass prairie, including the area of Hamden Slough. At one time, their range extended from south to north along the western edge of the state. But as more and more prairies were plowed, numbers dropped and the remaining prairie chickens were driven to inhabit either the high, dry beach ridges of glacial Lake Agassiz or low, wet ground-both unsuitable for the plow. The Minnesota DNR designated the greater prairie chicken as a species of special concern. The greater prairie chickens of Hamden Slough are thriving and visitors can hear their haunting booms every spring on the Hamden Lake lek. Reserve your spring morning in the Prairie Chicken Blind by calling the office at 218-847-4431.

When it comes to bird numbers on the Hamden Slough, shorebirds are second only to waterfowl. Up to 1000 shorebirds at one time have been observed using the refuge’s managed wetlands. Although migration boasts greater than 20 species, only the marbled godwit, killdeer, and greater yellowlegs breed on the refuge. The marbled godwit, a Regional Bird of Conservation Concern, uses wet prairies, grasslands, and marshes for breeding and nesting. These habitats are plentiful on Hamden Slough. During spring, it is likely visitors will hear the call of a godwit pair and see them flying low over the drained Hamden Lake.

Hamden Slough refuge lies on the eastern edge of the Prairie Pothole Region, an area that has experienced severe wetland declines. Since establishment, over 200 temporary and seasonal pothole wetlands have been restored; those most vulnerable to drainage. In addition, larger wetlands along County Ditch 15 were restored with management capability. Bisson Lake, a 112 acre marsh, is known for its spring and fall shorebird assemblages, as well as waterfowl breeding habitat. The “Big 6 Wetlands” total approximately 218 acres and provide a diversity of wetland habitats for waterfowl, shorebirds, and other wetland wildlife throughout the year. Staff continues to restore wetlands as land is acquired.

Two significant water bodies within the refuge acquisition boundary remain drained today: Hamden Lake and Pierce Lake. The original land survey maps describe the area as being open prairie with abundant wetlands and lakes, including a large “impassable marsh” named Hamden Lake. Hamden Lake, including both open water and marsh habitat, is estimated at roughly 1300 acres in size; about 1/5 of total refuge acreage after complete acquisition. Pierce Lake, another shallow lake, is currently under private ownership and when restored, is estimated to be nearly 300 acres. Both lakes were drained in the early 1900s with the construction of County Ditch 15.

The prairie soils of Becker County were described by early settlers for their richness “with no superior on the face of the globe” (Wilcox 1907). This discovery ultimately led to the conversion of tallgrass prairie to cropland. Today, only about 22 acres of remnant prairie remain on the refuge, in small, highly fragmented parcels. A focus of the refuge since inception is to put grass back on the landscape when land is acquired. Early on, cropland was planted to stands of grass. However, today staff restores cropland to a diverse mix of native grasses and wildflowers which provides benefits not only to nesting waterfowl, but a full range of wildlife.