Post by David Norris.— Reservoirs can offer us unique opportunities for fishing, but they also come with unique challenges to management. One such challenge is the formation of mudflats as reservoirs age. Mudflats are exactly what they sound like, expanses of mud or other fine sediment with little to no vegetation growth or hard structure.

Mudflat formation mostly depends on when, how regularly, and how drastically a reservoir’s water level changes. High water drowns terrestrial plants, while low water exposes and dries out aquatic plants. Even wetland plants may have difficulty becoming established by being flooded before their seeds have time to germinate and mature. If the fluctuations only happen every few years, we may not have a problem, as plants have a few growing seasons to get established before the next big change, but if these fluctuations happen annually, this area between high and low water (often called the regulated zone) becomes void of any significant plant growth. Any hard structures that are left in this area are subsequently buried by fine sediments that accumulate in the reservoir. In reservoirs with gently sloping contours, where large areas of lake bottom are exposed when the water is lowered, this can result in the formation of large expanses of mudflat. Pictured below: mudflats of Enid Lake, MS during low water.

Having a large empty mudflat is rarely good for us anglers. Many of the fish we like to catch (bass, crappie, etc.) like some kind of structure or plants to hide in. This isn’t just a preference of picky fish though. Vegetation beds support higher numbers of invertebrates (such as midge and dragonfly larvae) which are an important food source for both young sportfish and small baitfish. While vegetation is important for feeding our small fish, it also helps regulate the eating habits of the big lunkers we normally target. Giving those baitfish places to hide from Big Bubba Bass means they can live long enough to make more baitfish. Without the vegetation, Big Bubba Bass and his friends can easily eat themselves out of house and home, leaving no food for sustained growth. This leads to sportfish that are "big" lengthwise, but relatively skinny. Pictured below: well fed bass (top) vs skinny bass (bottom).

No one likes skinny fish, so improving fish habitat on mudflats is a prominent goal for reservoir managers and fishermen alike. It can also be quite labor intensive and expensive depending on the size of the mudflat. In my next few blogs we’ll discuss how we traditionally tackle this issue, as well as an alternative method that we’re currently testing. Stay tuned to see how managers and anglers can work together to improve our reservoir habitats!