
Acre for acre, Missouri’s wetlands rival any place on the planet in the amount of life they produce. Nearly half of the state’s 3,200 plant species are associated with wetlands, and more than a third of Missouri’s birds depend on wetlands for some part of their life cycle. Shallow wetland pools act as nurseries for the offspring of many amphibians and fish. The state’s most important furbearers — beavers, muskrats, mink, and otters — depend on wetlands for food and shelter. When compared to the Show-Me State’s wetlands, only tropical rainforests and coastal salt marshes produce more life per square yard.
But most Missourians miss all of it. And that’s a shame. Visiting a wetland, especially when spring migration is in full swing, offers the chance to witness wildlife spectacles that challenge anything you might see on the Discovery Channel.
Consider this article as both an invitation and a tour guide for visiting a marsh. Although entire books have been written about wetland wildlife, here we hit the highlights of what you might find on a visit to Missouri’s most productive habitat.
Show-Me Wetlands
When Charles Dickens visited America in 1842, he described the vast riverine wetlands surrounding St. Louis as “stagnant, slimy, rotten, filthy water,” and he called the area a “thoroughly distasteful and unhealthy place.”
Other folks saw wetlands not as wretched wastelands, but as wasted opportunities. They drained off the turbid water, plowed under the cordgrass and bulrushes, and used the rich soils to grow crops to feed an expanding nation.
Today, over 85 percent of Missouri’s original marshes and swamps are gone. But opportunities to visit high-quality wetlands remain in nearly every corner of the state (See Wandering Missouri’s Wetlands).
Something in the Air
You may notice a faint odor when you visit a wetland. The reason why is simple —marsh bottoms pass gas. A handful of oozy muck contains billions of bacteria and other microscopic creatures. These microbes make their living breaking down dead plants and animals. Most decomposers need oxygen to do their jobs. But wetland soils are often saturated, creating conditions where oxygen is in short supply. Luckily, some marsh microbes decompose organic matter using anaerobic chemical pathways. A byproduct of these reactions is hydrogen sulfide — also known as swamp gas — which has the unfortunate bouquet of a forgotten Easter egg rediscovered in June. If you wade through a wetland, you’ll notice clouds of tiny bubbles rising to the surface with each step, a miasma of microbial flatulence freed from the muck by your footsteps.
Since wetland soils stay soggy, wetland plants have evolved tissues that transport air from the atmosphere down to their waterlogged roots. If you were to cut a cattail or bulrush leaf in cross section, you’d see a network of tiny tubes. These are called aerenchyma, and they act like snorkels to passively move air from areas of high concentration (above the water’s surface) to low concentration (the plant’s roots).
Drying Out and Diving Down
Double-crested cormorants produce less oil than other waterbirds. When they dive for fish, their feathers eventually get soaked. Look for cormorants standing on stumps, holding their waterlogged wings out to dry.
Wet feathers are much less an issue for the pied-billed grebe. When a grebe gets spooked, it sinks underwater like a feathered submarine. Watch closely. The sneaky bird will resurface a little bit later when it thinks the coast is clear.
Much less concerned about being seen — and much more likely to be seen now than in decades past — is the bald eagle. Missouri’s wetlands provide eagles with open water and access to fish and waterfowl. Newly paired eagles build relatively small nests. Each year, the couple — which often remain together for life — add additional sticks to the existing structure. After several years, the nest can grow to gargantuan proportions. A nest in Ohio, for example, was used for 34 years until the tree it was in collapsed from the weight, which was estimated to be over 2,000 pounds.
Pelican Party
Weighing up to 30 pounds and with a 9-foot wingspan, a full-grown American white pelican is one of the largest birds in North America. If you spot a flock, it pays to spend some time watching their behavior.
White pelicans are one of the few birds that engage in cooperative hunting. Teams of pelicans paddle in a line, splashing water with their wings. Frightened fish swim away from the commotion — right into a trap. Once the pelicans herd the fish into the shallows or encircle the entire school, the hungry birds dip them up with their enormous, pterodactyl-like beaks as easily as if the fish were swimming in a soup bowl.
You may notice a round plate or “horn” on top of a pelican’s beak. Both males and females sprout these during mating season. They fall off at the end of summer and aren’t seen when the birds pass through Missouri during fall migration.
Hunting Herons and Hide and Seek
Herons and egrets have various tactics to catch dinner. Sometimes they wade slowly through shallow water, hoping to ambush unwary fish, frogs, and snakes. At other times, they stand motionless and wait for prey to swim within range of their long, flexible necks and dagger-like beaks. Green herons have been observed luring fish into striking range by dropping feathers or food into the water as bait.
If nature played hide-and-seek, American bitterns would win. To escape notice, the brown-streaked birds freeze and point their beaks skyward, virtually disappearing into the surrounding cattails and rushes. Spotting a bittern requires luck and determination. You have a better chance of hearing one, especially if you arrive at a wetland around dawn. Their call — a booming unk-a-lunk — can be heard half a mile away.
A Rainbow of Waterfowl
Like many birds, male and female ducks rarely look alike. Drakes have bright, colorful feathers to attract a mate. Hens have elegant but understated colors to help them stay hidden while they’re sitting on a nest. To illustrate the breadth of colors, males in breeding plumage are shown here.
Mallard
Mallards are the most common duck in North America. Nearly all farm-raised ducks can trace their ancestry to this widespread waterfowl.
Blue-Winged Teal
These small, sun-loving ducks migrate later than other ducks. On their way north, they linger in Missouri well into May.
Northern Pintail
Some pintails take travel to the extreme. One was recorded to have flown 1,800 miles nonstop.
Canvasback
These regal ducks are among the fastest of flyers. With a strong tailwind, they can reach speeds over 70 mph.
Scaup
Two kinds of scaup visit Missouri: greater scaup and lesser scaup. Good luck telling them apart! They look nearly identical.
Green-Winged Teal
Stretching only a foot from beak to tail and weighing only as much as a soup can, this dapper duck is North America’s smallest dabbler.
Northern Shoveler
Comblike ridges line the edges of this duck’s impressive beak. The ridges work like a spaghetti strainer, letting water pour out but trapping food inside.
Wood Duck
Wood ducks nest in holes high up in trees. A day after hatching, the ducklings follow mom to the entrance of the hole and jump out.
Common Merganser
Toothlike ridges on a merganser’s bill help it hold on to slippery fish, their favored food.
Gadwall
Gadwalls are often seen away from the shoreline, feeding in deeper water than other dabbling ducks.
American Wigeon
Wigeons eat more veggies compared to other ducks. Because their bills are so stubby, they can pinch harder, which makes it easier to pluck plants.
Hooded Merganser
Female mergansers often sneak an egg or two into the nests of other hens. Some nests have been found with over 40 eggs inside.
Ring-Necked Duck
Although they dive to find food, ring-necked ducks are often found in shallower water than most diving ducks.
Redhead
To attract a mate, redhead drakes bend backwards until their beaks touch their tails. Then they snap forward while giving a catlike mee-ooow.
Common Goldeneye
When goldeneye ducklings hatch, their eyes are brown. Over several months, they turn purple, then blue, then green, and — finally — golden.
Bufflehead
Chunky but tiny, female buffleheads
nest in abandoned woodpecker holes that other ducks can’t fit into.
Duck Designs
Biologists divide ducks into two basic groups: dabblers and divers. You can tell which group a duck’s in by the way it looks, flies, and feeds.
Dabblers
- Legs near the middle of the body make it easy for a dabbler to waddle around.
- Large wings allow a dabbler to burst from the water.
- A dabbler skims seeds and insects off the water’s surface. It also tips its head underwater to grab deeper grub.
Divers
- Legs that are far back on the body help a diver swim underwater but make it awkward on land.
- Skinnier wings cause a diver to pitter-patter across the water’s surface to get airborne.
- Divers — as the name suggests — dive underwater to nab fish or pluck up plant roots.
One Big, Honking Blizzard
Missouri is the halfway point on the Mississippi Flyway, a busy thoroughfare in the sky that ducks, geese, and other waterbirds follow to get from northern nesting grounds to southern wintering areas. Travel-weary birds gather in Missouri’s marshes to rest and refuel on their long journeys.
Among those using Missouri’s wetlands as migration stations are snow geese. Biologists estimate that the mid-continent population of snow geese ranges from 11 million to 18 million birds. Flocks containing well over 100,000 individuals are regularly seen in Missouri, and flocks of over a million have been counted at Loess Bluffs National Wildlife Refuge in northwest Missouri.
Traveling en masse is an effective survival strategy. The more geese in a group, the more eyes there are to keep watch while flockmates feed. If a lookout spots a predator — or an inquisitive human — it honks an alarm, and the whole flock erupts into flight like an upside-down snowstorm.
If you’re lucky enough to see such a spectacle, you may notice that not all snow geese are snow-white. Until 1983, the dark morphs, which have grayish-brown bodies and white heads, were thought to be a separate species.
Marsh Mammals
Most mammals come out after dark, so you aren’t likely to see many in the flesh and fur. But footprints left on muddy banks offer clues of their presence. With a good field guide, it’s easy to identify the tracks of common wetland denizens like raccoons, otters, and mink. If you’re lucky, you may even find more permanent signs left behind by two of Missouri’s most industrious mammals: beaver and muskrat.
Tree stumps that look like they’ve been run through a pencil sharpener indicate the efforts of the Show-Me State’s largest rodent. Using only its incisors, an American beaver can drop a willow tree that’s thicker than your leg in under 5 minutes. The buck-toothed builders gnaw on trees for food and use the branches to build dens and dams.
Muskrats, the beaver’s pint-sized cousins, mow down patches of aquatic plants, bite by bite. This creates areas of open water where fish, frogs, and turtles can swim, herons can wade, and ducks can land. Uneaten leaves and stems are used by the furry “marshchitects” to construct mound-shaped dens and feeding platforms. Look for 4-foot-high heaps of mud-spackled vegetation dotting the marsh.
Spring Symphony
Far from being silent and serene, a cacophony of sounds ricochets around a wetland. If you listen closely, you’ll hear spring in full swing as a chorus of amphibian love songs overflows each shallow pool.
The spring peeper’s peep, peep, peep (like the ping made by striking the high note on a xylophone) harmonizes with the chorus frog’s crrrreeeeeeep (similar to the sound made by running your fingernail over the teeth of a comb) and the American toad’s brrreeeeeeeee (a high-pitched, musical, drawn-out trill) to provide a natural, musical tour de force.
Not ‘Distasteful and Unhealthy’ at All
Missouri’s wetlands ooze life from every soggy nook and cranny. They play a vital role in the continued well-being for wildlife throughout Missouri and large swathes of North America. Charles Dickens may have thought them “distasteful and unhealthy” at first glance, but with a little perspective, he may have realized that visiting Missouri’s wetlands are among the best of times.
Wandering Missouri’s Wetlands
While most of Missouri’s original wetland acreage has been lost, the state’s patchwork of wetlands in conservation areas and National Wildlife Refuges provides species with the food and shelter needed for survival. Most Missourians are a relatively short drive from a wetland.
To protect migrating waterfowl, portions of some conservation areas may be closed to the public from fall through early spring. Before you go, it’s smart to review the specific area’s policies in MDC’s online atlas at mdc.mo.gov/atlas.
When to Go
Spring is a fantastic time to visit a wetland. In March, ducks and geese flock to wetlands on the northward leg of their annual migration. In April, pelicans pass through, and a variety of herons and other long-legged waders arrive. In May, shorebirds skitter across mudflats, while willows and cottonwoods drip with warblers and other colorful songbirds.
What to Bring
- A pair of binoculars brings distant critters in for a closer look.
- Birds, bugs, and blooms abound in wetlands. Field guides help you learn what you’re looking at.
- Wetlands are wet (obviously!) and muddy. If you plan to explore outside your vehicle — which you should — wear a pair of waterproof boots.
- Mosquitoes love marshes. Keep the bloodsuckers at bay with insect repellent.
- If you’re bringing kids along, a mesh aquarium net will strain up squiggly, captivating creepy-crawlies that lurk in wetland water.
Matt Seek is the editor of Xplor, MDC’s magazine for kids. A version of this article appeared in the March-April 2024 issue of Xplor. Matt grew up on Fountain Grove Conservation Area, an 8,000-acre wetland.
Life squishes out from every saturated corner of Missouri’s wetlands
































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This Issue's Staff
Editor – Angie Daly Morfeld
Associate Editor – Larry Archer
Photography Editor – Ben Nickelson
Staff Writer – Kristie Hilgedick
Staff Writer – Joe Jerek
Staff Writer – Dianne Van Dien
Designer – Marci Porter
Designer – Kate Morrow
Photographer – Noppadol Paothong
Photographer – David Stonner
Circulation – Marcia Hale