Wetland Enhancement for Wildlife (by DK)

I am often asked about wetland features to increase use by wildlife. After observing wetlands of many types in Wisconsin for more than 45 years I do see features that attract both game and non-game animals. Here in Dodge County we have acidic bogs, grass and shrub carr marshes, river flood plains and wet eutrophied lake bays. Often the marshes are abandoned farm land that has not been worked for decades since horse drawn equipment and/or organic soil decomposition lowered the fields below seasonal dryness. Some of these nearly abandoned fields have a dense cover of Reed Canary Grass that is harvested during the drier years leaving little good wildlife habitat especially if the grass is harvested before bird nesting and rearing is complete. Within these dense stands of Reed Canary Grass, even if never mowed, it is difficult to establish other forbs and woody species. Given many years you will see some establishment of Dogwoods, Willows, Goldenrods and Asters. If the marsh has wetter areas with hummocks and Cattails that were always nearly impossible to till you may see Coreopsis, Polygonums, Bottle Gentian, Marsh Marigolds, Blueflag Iris and several other species near the edges of these Cattails as the land rises just a little to the grasses. Once Dogwoods and Willows get a foot hold they are able to compete by shading out the Reed Canary Grass. If by chance the marsh has areas that are just a little higher acting as low islands


Willow intrusion 15 years after mill dam removal

you may see Nannyberry, Quaking Aspen, Green Ash, American Elm and Hawthorn. Twining and climbing over these you may find Wild Grape and Wild Cucumber. All of these species provide great cover and food sources for wildlife. Nannyberry is a favorite of Deer, these slightly higher islands provide a view of the marsh and good bedding spots while hidden by the cover. Game and song birds also find nesting sites, food and cover in the shrubs and trees. At the same time open marsh areas are close by for feeding and hunting. 




Example of cover trees and shrubs

To enhance a marsh that is pure grass cover you should take a good walk about the site. Scout for the wettest and driest areas, look for animal trails and cover fence rows or uplands adjacent to the marsh that act as possible corridors for wildlife. If the marsh happens to have a pot hole, spring or small stream you have a natural attraction for all the animals nearby. Try to provide an access to the water with a little cover spot, a few shrubs and a tree or two. On those slightly higher spots you can provide another island of shrubs or a few trees. Along the edges of wetter areas you can add a few forbs to provide seeds, nesting material and cover. Marshes in more northern counties have a large evergreen component with Black Spruce, Balsam Fir, White Pine and Tamarack. The shrub layer can be either Willow and Dogwood or Speckled Alder, Winterberry Holly, Black Chokeberry and Spirea depending upon the pH of the soils. The Alder thickets make good habitat for Black Bear due to the berries of Raspberry, Dewberry, Blueberry and the large ant mound colonies on just slightly drier ground. I also see Sharptail Grouse on the fringes of these wetlands. Along river flood plains you should observe whether your site is along the erosional or depositional side of the stream. Meandering stream flood plains may have both in just a short run of the stream. The meandering Crawfish River here in Dodge County has a very different life community on the erosional versus depositional stream banks. You would see pioneer species along the depositional banks, young Green Ash, Boxelder, Silver


Sandbar willow as a stream bank stabilizer

Maple, Willows, River Birch and many sun loving forbs. These provide a good variety of game foods and cover for small animals and birds. Along the erosional banks you see mature forests of Bur Oak, Swamp White Oak, Hackberry, Gray Dogwood and Hawthorn. Wild Grape and Virginia Creeper climb in the shrubs and toward the canopy of the large tress. Here you find Squirrels, Owls, Hawks and Wood Peckers because these animals need tree cavities or high perches for nests. The predators have great vantages to see Mice, Rabbits and other prey along both sides of the stream. You may add forbs, shrubs and trees along these banks to enhance cover. You may also want to leave some stretches of the banks with just low forbs and grasses that give pleasant views of the stream.
The bogs and eutrophied lake bays are probably in pretty much original pre-settlement conditions. In these areas you may just want to keep an eye out for invasive species and anything that might damage the shoreline or drainage of the area. These areas have many species unique to unspoiled wetlands.
Another type of wetland that I see along the upper Fox River and lower Peshtigo River are on very sandy ground. In these wetlands there is a high variation of the water table seasonally. There are odd combinations of plant species here, Jack Pine

Pitcher plant and leather leaf

and Speckled Alder or Red Oak and Winterberry Holly. Restorations in these sites would be very interesting to watch over the years just to see what thrives.
You may start grandly or timidly to add enhancements, then enjoy the new plants and animals that find your additions and management projects.