Long ago, most of northwest Ohio consisted of the Great Black Swamp, a 1,500 square mile swamp stretching from Port Clinton to Fort Wayne, Indiana. Now, much of that area is farmlands, but there are efforts to restore some of the region to its original state. One such spot is a complex of wetlands along the Toussaint River, just south of the Ottawa wildlife refuge.
The project, part of a larger restoration effort in the area led by The Nature Conservancy (TNC), began in 2016 with the goal of connecting the wetlands to the nearby Toussaint River and opening the area to nutrient exchange and fish habit. Partners included Ohio Sea Grant, Ducks Unlimited, Black Swamp Bird Observatory, the Ohio Department of Natural Resources and the National Oceanic and Atmospheric Administration.
Ohio Sea Grant did preliminary work to assess the area so that it could be compared to post-restoration conditions. This helps agencies determine if the actions they took had the desired effects, such as bringing fish back to an area or helping filter nutrients out of the river before it enters Lake Erie. Extension Program Manager Tory Gabriel’s team surveyed prerestoration fish populations.
Gabriel used two sizes of trap nets to capture a variety of fish and get a precise estimate of the population, but that’s far easier said than done. One goal of the larger project is to improve accessibility to the wetlands, but Gabriel and his team didn’t have the luxury of waiting until improvements were made. The team often had to deal with downed trees blocking access for their trucks, requiring them to carry heavy buckets of water and fish to and from the work area, and simply moving across the slick, gloopy wetlands was difficult.
The wetlands restoration project is currently finishing phase 1, which removes interior dikes, connects the area to the Toussaint and constructs a new water control structure, transforming the landscape from a series of isolated wetlands into a single large wetland connected to the river. The water control structure is especially important as it will allow water quality managers to change the water level as needed and will provide a tool to help control invasive European Reed (Phragmites).
Phase 2 establishes exterior dikes to protect the marsh and surrounding area from erosion. Once that’s done, Gabriel expects to come back to determine how the restoration affects fish populations, just as he did with previous parts of the larger TNC project.
Restoring the wetlands is an important step to improving the health of Lake Erie. Wetlands slow down the flow of water from the river, which means some sediments and nutrients will settle in the marsh rather than the lake. Reducing the amount of nutrients flowing into the lake will help prevent excessive algae growth and is essential to curbing harmful algal blooms and hypoxia (when water near the lake bottom runs out of dissolved oxygen).
Restored areas will also serve as a refuge for bird and fish populations. Little fish need a safe habitat so they can grow, and wetlands provide an excellent refuge from predators. “The hope is for increased species diversity,” which contributes to a healthier ecosystem overall, said Gabriel.
Many of the paths into the marsh are also being cleared and reformed, which should alleviate many of the current difficulties for traversing the wetlands. That’s especially great news for birdwatchers, as birding is already popular in the region – the Black Swamp Bird Festival takes place there each May and features tours through nearby birding sites.
It will still be a while before the restoration is fully completed. Once it is, TNC would like to further expand their restoration efforts, continuing their mission of preserving the natural ecology of northwest Ohio, and when the next project starts, Ohio Sea Grant will be there with nets and buckets, ready to get dirty.