Minnesota Outdoors: Blane Klemek on degraded wetlands
I recently had the pleasure of working with United States Fish and Wildlife Service (USFWS) Private Lands Biologist Kurt Svendsgaard on a wetland restoration project on my property. Two small adjoining temporary wetlands about one-acre in total size had been ditched by previous landowners’ decades ago. The dredged ditch, about two and a half feet deep and three feet wide coursing through both wetlands, effectively drained the small basins into Assawa Lake. And ever since I’ve lived here, almost 20 years now, I’ve wanted to restore the degraded wetlands.
Enter USFWS’ “Partners for Fish and Wildlife Program” and Kurt. I e-mailed Kurt one day earlier in the summer with my simple proposal of placing an earthen dike across the ditch where the ditch outlets the basins. A short time later, Kurt stopped by for a look at the two wetlands. Equipped with aerial imagery and knowledge from previous in-office evaluations, Kurt determined that two dikes should be constructed at specific locations to maximize the former integrity of the wetlands.
A month or so later after a contractor had been found and agreed to do the job, both Kurt and the contractor showed up to construct the dikes. Operating a compact excavator, the contractor, through Kurt’s instructions, constructed the two dikes in less than three hours. And already there’s water pooling behind both dikes within the centers of the wetlands.
Stealing a line from the popular film “Field of Dreams” certainly holds true for the restored wetlands: “If you build it, he will come.” Already—and it’s only been a little over a week—waterfowl and other wetland dependent birds are using the wetlands as Nature intended. Now functioning as wetlands should function, both basins are once again attracting birds and other wildlife.
Next spring following snowmelt the wetlands will prove to be especially critical to migrating waterfowl and other wetland birds. Up to a foot of water, possibly a little more, will pool in both of the small wetlands. A flush of invertebrates will provide abundant sources of protein-rich food for ducks and other wildlife. Frogs and toads will be enormous benefactors of the restoration, too. Wood frogs, chorus frogs, spring peepers, gray tree frogs, and American toads, to name some, will be vocalizing loudly from the wetlands come springtime. Eggs will be laid and tadpoles will hatch and develop into their adult forms.
Sure, there’ll be hatches of mosquitoes, but also hatching from the wetlands will be predatory damselflies and dragonflies. Additionally, one can expect a multitude of other insect species preying on mosquito larvae within the water itself. Bats at night and insectivorous songbirds during the day will find suitable hunting grounds above and within the sedges and edges of the newly restored wetlands, too.
A few days ago while walking on my wooded trail alongside the two wetlands, I heard an unusual croak from some kind of bird. I recognized the vocalization as heron-like, but I couldn’t locate the bird right away. After taking a few more steps, the bird flushed from its perch on top of one of the two dikes. The bird was a green heron. Flying over the wetlands in front of me, croaking the entire way, it landed in vegetation near a clump of willows a short distance from where I stood.
After the heron landed, another couple of croaks emanated from a nearby patch of sedge and grasses. There were two green herons, and the one didn’t appreciate the other being there. The trespassing heron was immediately chased away by the resident green heron, and so the trespasser flew into a tree near where it had flushed from the dike only a moment before. Croaking incessantly, I couldn’t tell if the heron was vocalizing its displeasure at me or the mean heron at the other end of the wetland. Maybe both of us.
Wetlands are wonderful. They’re life-giving, natural water purifiers, and are invaluable on the landscape for water retention and flood mitigation, not to mention of course their supreme and intended value to wetland dependent species of wildlife as we get out and enjoy the great outdoors.