The Museum Wetlands and freshwater mussels
November 15, 2021
As you walk the path alongside the wetlands at the Museum of Life and Science, you are likely to see some animal species that come from the phylum Mollusca. This diverse phylum includes snails, slugs, clams, octopi, cuttlefish, squids, and mussels. These animals can live in a variety of habitats, including wetlands, making some more likely to be spotted than others. But it isn’t just snails and slugs we have living in the water that runs through the wetlands. It is likely we have some freshwater mussels either in the water on grounds, or nearby in Ellerbe Creek. There are about 60 species of freshwater mussels or clams living in North Carolina, and unfortunately, over 50% of them are threatened or endangered according to the NC Wildlife Resources Commission.
Freshwater mussels are key to understanding the health of the water where they reside. As an indicator species, their well-being reflects the overall well-being of their ecosystem. Freshwater mussels filter water continuously and are an essential food source to many other species living near them, such as muskrats, great blue herons, raccoons, minks, and more. Keeping the number of freshwater mussels high is crucial for all the other animals and plants around them that rely on a stable food web and clean water.
Freshwater mussels come in all kinds of shapes, colors, sizes, and textures. Some live for many years, some can make pearls, and some are endemic, meaning they only live in a few water systems. For all their differences, there are also many similarities between all the species. They all live in the substrate at the bottom of freshwaters like creeks, lakes, rivers, and wetlands. Many species rely on the gills of fish to move their larvae for them in order to spread as they reproduce. They all filter feed by letting the water run over their open gills and eating microscopic bacteria, plankton, and zooplankton. However, not everything that enters the freshwater mussel gills is eaten. Some material is removed from the water, moves through the mussel, and is deposited into the ground below them; this helps keep the water clean.
Unfortunately, there are many threats to freshwater mussels. Human constructed dams stop the flow of oxygenated water and can separate freshwater mussels from the fish that are needed for reproduction. The introduction of non-native species means that native species are often out-competed for space, oxygen, and food. Pollution and sedimentation bring in small particles that can get into the freshwater mussels and have devastating consequences. Historically, humans collected huge numbers of freshwater mussels to use their shells to make buttons and to sell their unique pearls. The habitats of freshwater mussels are threatened by human encroachment as roads, buildings, and other infrastructures get built close to their habitats.
The wetlands at the Museum potentially provide a habitat for freshwater mussels. Even if there are no mussels on the grounds, however, they are impacted by the water flowing through the wetlands. Watersheds are a similarly beneficial water filter to freshwater mussels. By taking good care of our surrounding environment and the wetlands here on campus, we can demonstrate the importance of clean water. When water flows into wetlands, it slows down and the plant’s roots provide surface space for the sediment in the water to sink into the ground and clear up the water. The healthy plants we have growing in the wetlands help to cycle the nutrients properly through the water, keeping the water system in balance. By taking good care of the wetlands here on the Museum campus, we can demonstrate the value of clean water.
Healthy water for humans relies on an abundance of freshwater mussels helping filter our water in nature. For the safety and cleanliness of water sources, as well as those ecosystems as a whole, protecting freshwater mussels from further decline is critical. Keeping freshwater mussels safe relies on humans. We must all work to keep trash, chemicals, and other material out of the water, as it can get into the watershed and spread, harming many species. We can learn about local species and where they are located, and be extra careful when playing in the water to not disrupt the mussels. It is important to become knowledgeable about non-native species and help to make sure that they are not being introduced in even more water systems. Ensuring protection sometimes relies on contacting elected officials and letting them know the value of mussels held in local water systems and asking for legislative action and funding.
Lastly, we can ensure that other people know about freshwater mussels by sharing our own knowledge with them and helping everyone see their importance on the health of our ecosystems. By working at the Museum and helping share our wetlands, you are creating a community that embraces the conservation of local species.