A common visitor to the Mingo Swamp is the wood duck. Wood ducks begin nesting in the Refuge’s tree cavities in March – April. The refuge offers ample nesting cavities in or near water. Shallowly flooded habitat with good understory cover; such as shrub-scrub or emergent vegetation, is the most important habitat for wood duck broods. Wood ducks feed on a variety of plant and animal food such as acorns and invertebrates, which are readily available on the refuge. Wood ducks can be seen near the Swampwalk Nature Trail when it is flooded or on the Mingo River.

Once known as the “Golden Swamp Warbler,” the beautiful bright yellow and dull grey songbird is quite a treat to see on the refuge. It is a migratory bird that breeds and nests in tree cavities over water and eats insects. Prothonotary warblers are good indicators of healthy bottomland forests and can be seen flitting about on the Swampwalk Boardwalk in the summertime if one walks quietly.

A resident of Mingo’s cypress swamps and sloughs is the western cottonmouth. Like all snakes, the cottonmouth is shy and prefers to avoid human interaction. It is one of Missouri’s five venomous snakes. The cottonmouth is a beautiful creature that is best viewed from a distance and they will move on in a matter of minutes. The cottonmouth gets its name from the white lining inside of its mouth and is seen when it opens its mouth as a defensive pose. This snake likes the warmth of the road so please be alert while driving on the refuge and avoid any snakes crossing the road.

A very unique prehistoric fish, the Alligator gar is the largest freshwater fish in North America and can grow up to 10 feet long and weigh up to 300 pounds. It is the only mature gar to have dual rows of large teeth in the upper jaw. Alligator gar feed as scavengers and only eat invertebrates and dead carcasses, and act as stewards of clean and healthy water systems. Historically, Alligator gar were present in the bootheel; lurking in slow river systems, brackish pools, and bottomland wetlands. Unfortunately, dams and dikes have altered their riverine ecosystems and eliminated their spawning habitats in floodplain wetlands. A reintroduction program on the refuge with the Missouri Department of Conservation in 2009 released 275 Alligator gar fingerlings in hopes of one day restoring this rare fish back to its native stomping grounds.

A century ago the Missouri bootheel was a vast 2.5 million acre bottomland hardwood forest. Today, Mingo National Wildlife Refuge has the the largest remaining tract in the bootheel with 15,000 acres of bottomland hardwoods.

Cherrybark oak, swamp white oak, swamp chestnut oak, Shumard oak, pin oak, willow oak, overcup oak, shagbark hickory, and water hickory are important food and cover sources for many wildlife like deer, waterfowl, squirrels, turkeys, fox, and bear. These trees are commonly found on the refuge in the bottomland hardwoods and tolerate short term flooding during the dormant season. Bottomland hardwood forests are one of the lowest and wettest types of hardwood forests and acts as a transition between the drier upland hardwood forest and wet floodplains and forested wetlands. 

The swamp forest ecosystem found on the refuge are filled with water most or all of the year have two primary tree species, bald cypress and water tupelo; species that have adapted to the flooded conditions of their environment. Cypress trees have “knees” that extend from their root system to above the water level. It is thought they are used as anchors and are a means of respiration for the tree. The trunks of bald cypress and water tupelo trees often have swollen bases and the height of the swollen base is a response to flooding where there is continual wetting and soaking of the trunk. These trees offer cover and food for wildlife, including butterflies and bees.