Guide to Significant Wildlife Habitat - Door County Web Map

commercial fishermen. Seventeen species of fish have been identified in the river or the adjoining
bay. However, no net surveys of non-game fish have been conducted in the Mink River.
There has been neither survey of mollusks nor evaluation of the biotic index of the river based on
aquatic invertebrates.
• The dynamics of the wetland communities are driven largely by the short and long-term fluctuation in
lake level. The wetland communities can be broken into five main categories: The emergent [or
deep] marsh along the Mink River; A shallow marsh characterized by an even mixture of the sedges
Carex aquatilis and C. prairea forming extensive sedge meadows that fringe the spring-fed channels
upstream; A wet meadow dominated by sedges Carex stricta and Calamagrostis canadensis that
border the entire marsh; The interface between the marsh and the surrounding upland which is
inhabited by a mixture of small trees, shrubs, and herbaceous wetland species; And the lowland
forest of white cedar, alder, black ash, and tamarack.
• The northern sedge meadow mentioned above is a rare to uncommon community in Wisconsin as
many of these sedge meadows have been lost to grazing or drainage. The relatively board expanse of
this meadow area near the headwaters of the Mink River is also significant as most sedge meadows in
northern Wisconsin are limited to narrow strips between deeper water marshes and a surrounding
shrub carr.
• With water levels near the soil surface fed by alkaline springs, the Mink River sedge meadow is the
breeding site of the federally endangered Hine’s Emerald dragonfly (Somatochlora hineana).
Because of the dolostone bedrock below, the sedge meadow area supports species more often
associated with fens such as brook lobelia (Lobelia kalmii) and marsh-bellflower (Campanula
aparinoides).
• Mature fruits of the abundant sedge plants are food for some bird species and contribute to the
desirability of the Mink River habitat for the rare Yellow Rail, a species considered to be critically
imperiled in Wisconsin. The Sedge Wren is a special concern species in the state and appears to be
abundant in the sedge meadow area.
• The deep marsh at the Mink River is also valuable to the avian community. Especially during fall
migration, waterfowl are attracted to the area to forage on the seeds of wild rice (Zizania aquatica),
bulrushes (Scirpus americanus and S. validus), and bur-reeds (Sparganium spp.). Common breeding
waterfowl include Blue-winged Teal (Anas discors), Mallards, and Wood Ducks. While not as
common as the preceding species, American Black Duck (Anas rubripes), Northern Pintail (Anas
acuta), and Common Merganser (Mergus merganser) have nested in the Mink River wetlands. Other
rare birds associated with the Mink River wetlands include Black-crowned Night Herons and Caspian
Terns. The terns are listed as endangered in Wisconsin and nest on islands in Lake Michigan and use
the river for foraging. American Bitterns (Botaurua lentiginosus), Double-crested Cormorants
(Phalacrocorax auritus), Yellow Rails, and Great Blue Herons also use the wetland area. Northern
Harriers, Goshawks, Cooper’s Hawk, Red-shouldered Hawks, Osprey and Bald Eagles have all
recently nested in the forests surrounding the Mink River.
• The most abundant forest type surrounding the Mink River is the northern wet-mesic forest. Seasonal
pooling and an abundance of bryophytes and liverworts characterize the northern wet-mesic forest,
dominated by white cedar and balsam fir standing in a swampy substrate. The conifer swamp at the
Mink River is the habitat of at least four rare orchids. Three of these orchids: white adder's-mouth
(Malaxis monophyllos var. brachypoda), showy lady’s-slipper (Cypripedium reginae), and large
roundleaf (Platanthera orbiculata) are listed as species of special concern in Wisconsin due to rarity.
Mink River / Rowley’s Bay System 117