For many, wetlands are nice to look at but are otherwise mysterious places. Few people dare to tread through the water, mud, and muck that defines them. Staying on dry land is preferable, but without these wet elements of our landscape, our world would not benefit from the numerous functions and values that wetlands provide. Wetlands are a gift to most wildlife and certainly to humans, if only we paid attention.
For coastal humans, tidal wetlands are especially important as barriers to storms, and nurseries for much of the seafood we value. But beyond that, most of us know little about what goes on in the sea of grasses and sedges we see from bridges or from boats as we float by. Let me share a few tidbits of why they are important and need our protection.
Wetland scientists promote several functions and values of wetlands. These terms may seem similar, but there are distinctions. A function is an action performed regardless of who or what benefits. Tidal wetlands, for example, serve to protect adjacent uplands from flooding and erosion, benefiting the upland habitat and any organisms that live there. A value, on the other hand, typically refers to how something directly benefits humans.
In addition to protecting shorelines and inland habitats, tidal wetlands also function as nursery grounds for a multitude of marine and freshwater fish and shellfish, where their young benefit from the nutrient rich waters and marshes and the protection from predators that these shallow habitats provide. Waterfowl and other types of wildlife use them throughout the year for breeding and overwintering.
Humans certainly benefit from their role in buffering our homes and communities from winds and waves of winter and tropical storms. We benefit from the nursery function of tidal wetlands every time we dine on seafood. We also benefit from mitigation of water quality by coastal wetlands. Beyond that we also value these wetlands for recreation, like boating, hunting, fishing, or simply observing nature.
But, what we do not always value is their continued existence. Although they are protected by state and federal laws, we often find ways to work around those, resulting in an ever-shrinking inventory of tidal marshes. We are sadly loathed to recognize the consequences of these losses. There are examples at both small and large scales.
For homeowners along beaches, bayfronts, or bayou shorelines, those natural bands of marsh grass impede our access to water where we walk or park our boats. The result is erosion and the need to build bulkheads to shield what those lost marshes used to protect.
On larger scales, science knows why we have lost hundreds of square miles of tidal marshes across the Mississippi River deltaic plain in Louisiana because of the actions of oil and gas extraction and the overuse of levees. Those marshes were historically fresh in nature before we intervened, fed by massive amounts of freshwater and nutrients flowing from the Mississippi River Watershed.
To protect our communities and support shipping, we built levees to prevent flooding and maintain adequate channels that prevent water, and the sediments and nutrients it carries, from reaching marshes. These wetlands sink under their own weight and without regular renewal of thin layers of sediments, they sink and disappear. Channels cut for oil and gas exploration allows saltwater intrusion, killing fresh marshes.
And although we know how to counter loss of these wetlands, we do little about it. Politics, for example, has recently stopped the science-based Mid-Breton Sediment Diversion project that would have helped demonstrate how we could reverse these losses.
The lesson here is we all need to understand how wetlands of all kinds benefit us. Only then can we advocate for their protection. They are a gift worth saving.
Hope to see you in our great outdoors!