No one has battled a bad reputation as intensely as wetlands, especially in the United States. Before settlers arrived, over 220 million acres of wetlands could be found across the country. For Native Americans, villages were often located in close proximity to wetlands for food and resources. They saw wetlands as “gardens” and recognized the value of managing and honoring these life-sustaining habitats. As settlers moved west, more wetlands were drained for cropland, and wetlands were viewed as disease-ridden swamps to be eliminated. I like to think that wetlands are just the misunderstood middle child doing their best in a thankless and often forgotten role.
Wetland vegetation emerging in the spring in an eastern Oregon wetland system.
What is that role, you might ask? Wetlands have many important functions within the natural world, and they directly benefit humans and wildlife. Even if you don’t look at a wetland to admire its beauty (although many people do) I promise they are worth appreciating– and thanking. One of the most important benefits, particularly in the western United States, is that wetlands provide water storage. Slowing the movement of water through a system reduces erosion, and it allows water to seep further underground and recharge the aquifer. This supports groundwater resources and promotes water filtration. Some wetlands are even constructed for the sole purpose of filtering wastewater! These “constructed wetlands” use natural processes to treat sewage, stormwater runoff, and other potentially poor water quality sources. Plant roots and microorganisms that call wetlands home actively remove excessive nutrient runoff and other potentially dangerous pollutants from getting into our water sources. You also may be overlooking that these ‘sluggish’ systems are hotspots for biological productivity (and diversity). They provide habitat for wildlife and invertebrates of all kinds, including supporting fisheries and shellfish industries.
An example of a constructed wetland designed to treat nutrient runoff (left),
essential wetland functions (right)
From an ecological perspective, wetlands are crucial to maintaining migratory pathways for waterfowl and migratory birds. Within the Pacific Flyway (spanning from Alaska to Patagonia), wetlands provide breeding, wintering, and stopover habitats that are increasingly threatened by climate change and land-use. Think of wetlands as gas stations and the flyway as interstates and highways along the west coast. If gas stations dry up along the highway, the distance between these refuges becomes longer– sometimes too long. This makes the journey more strenuous and can cause strandings. Wetlands provide a mosaic of “rest stops” where waterbirds can refuel and rest before continuing their journey. Spatial ecologists are particularly concerned with wetlands in southern Oregon and northeast California continuing to sustain connectivity due to the influence of climate change.
Long-billed dowitcher (Limnodromus scolopaceus) taking advantage of a wetland system (left; photo credit Peter Pearsall), graphic of Pacific Flyway (right; credit Perky Pet: learn more)
Let’s back up to the definition of a wetland: it’s wet (duh). This is true, but wetlands are not necessarily wet all the time. There are temporary (also called seasonal) wetlands that bolster the connectivity during migration in the spring & fall. Additionally, there are permanent (always wet) wetlands that have recently been transitioning into more temporary wetlands, which decreases overall available habitat and connectivity. Fortunately, agricultural practices in the Central Valley of California and in southern Oregon can also support waterbirds, although agricultural land is more susceptible to economic pressures and water scarcity concerns that often overrule wildlife needs.
There is substantial work being done by federal, state, and local agencies to mitigate these concerns. Environmental organizations, including nonprofits like us, are continually working to improve the restoration and management of wetland systems. RRWC works on river restoration projects, but the benefits of our projects extend to wetlands, albeit indirectly. For example, our projects work to ensure that surface water and groundwater resources are connected. This allows for a more resilient floodplain, including wetland ecosystems. Our projects also seek to reduce erosion, which decreases the buffering needs of wetlands along the way. By slowing down the water within systems, we are decreasing the impacts of turbidity and creating a natural environment that is more self-sustaining. Remember, taking pressure off the middle child will benefit everyone!
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