New Strategies for Restoring Coastal Wetland Function, Maumee River Area of Concern
Project Start Date
Description of Work U.S. Geological Survey (USGS) scientists are focusing on restoring natural water flow and ecological processes between coastal wetlands in the Ottawa National Wildlife Refuge (Ohio) and adjacent to Lake Erie to improve fish and wildlife habitat. This pilot project will develop approaches that will restore coastal wetland function and increase ecosystem resilience to be used as a model throughout the Great Lakes basin. USGS will focus on restoring natural hydrologic processes in diked coastal wetlands adjacent to Great Lakes waters to improve wetland functions like phosphorus retention and restoration of habitats for fish and wildlife. Sustainable approaches are being developed in the Maumee River Area of Concern [...]
Description of Work
U.S. Geological Survey (USGS) scientists are focusing on restoring natural water flow and ecological processes between coastal wetlands in the Ottawa National Wildlife Refuge (Ohio) and adjacent to Lake Erie to improve fish and wildlife habitat. This pilot project will develop approaches that will restore coastal wetland function and increase ecosystem resilience to be used as a model throughout the Great Lakes basin. USGS will focus on restoring natural hydrologic processes in diked coastal wetlands adjacent to Great Lakes waters to improve wetland functions like phosphorus retention and restoration of habitats for fish and wildlife. Sustainable approaches are being developed in the Maumee River Area of Concern (AOC) to restore the hydrology and other processes that drive coastal wetland functions and increase ecosystem resiliency. Results will be evaluated within an adaptive management framework and integrated with similar sites in the Saginaw River/Bay AOC and throughout the Great Lakes basin. Since the connection to the wetland was restored, the abundance and diversity of fish using the wetland habitats has exploded. Northern pike and other recreationally and commercially valued species are again using the 40 ha wetland for reproduction and feeding. Bird usage by waterfowl and several listed species is extensive. Preliminary water-quality data indicate that the water exiting the wetland back into the Maumee River AOC had significantly less phosphorus and other nutrients than the incoming water, which has very positive implications for the water quality BUI for the Maumee River AOC. Additional samples taken through FY 2013 will characterize the spatial and temporal patterns of fish use, nutrient retention, and other important wetland processes. Coordinated efforts with the coastal wetland monitoring program, data collection efforts identified in Remedial Action Plans, NOAA-funded habitat restoration projects, and The Nature Conservancy to help guide regional restoration strategies and maximize basin-wide impact of locally-important projects.
Relevance & Impact
The reconnected wetland continues to be a sink for phosphorus, nitrogen, and sediment from Crane Creek. High levels of sediment and nutrient retention (~50%) have been observed during the passage of storm or flood events that move large quantities of water into the wetland. These data show the potential water quality improvements associated with this type of wetland restoration and provide baseline data that can be used to promote further restoration efforts in the Maumee AOC and other Great Lakes coastal areas.
The results of this study have led to further wetland reconnection projects throughout the Great Lakes basin. Numerous GLRI projects have included water-control or fish-passage structures as a direct result of our work, and the ongoing monitoring at ONWR has helped shape wetland management decisions regionally. Although focused on the Crane Creek coastal wetland complex from 2010-2012, the results of this work are influencing regional management and restoration decisions and supporting expanded landscape-level analyses in 2013.
Fish diversity and abundance in the restored wetland has increased dramatically in the two years since reconnection. The wetland has been acting as a nursery and breeding grounds for many species including: northern pike (Esox lucius), largemouth bass (Micropterus salmoides), white and black crappies (Pomoxis spp.), and numerous species of sunfish (Lepomis spp.). High resolution sonar data have shown that fish access the wetland at all times of the day from late winter to late autumn. Data on fish species richness and abundance changes could be used to identify progress toward delisting of the “Degraded Fish and Wildlife Population” BUI in Maumee River AOC. Discussions with Ohio EPA and Partners for Clean Streams are helping guide analysis of existing data and data collection strategies in 2013.
Invasive common carp were effectively excluded from the restored wetland habitat during their destructive spawning stages through the use of specially designed gates in the water control structure. By using an established bar width and excluding mature breeding size carp, integrated pest management approaches were applied to limit the risk of damage by invasive carp while still allowing northern pike and other native fish to pass into the wetlands. Similar technologies are being included in many other GLRI-funded coastal wetland restoration projects in western Lake Erie and Saginaw Bay, Lake Huron.
Waterfowl and piscivorous bird usage of the wetland increased after being reconnected to Lake Erie. The availability of wetland habitat was crucial in 2012 when low water levels stranded some coastal wetlands and drought conditions contributed to dry conditions in many diked wetlands in the area. However, the reconnected wetland held water throughout the summer and was used extensively by migrating waterfowl in the autumn.
A model was developed to estimate total phosphorus and total sediment loads to the reconnected wetland using high frequency turbidity and discharge measurements. This allows for more accurate estimates of nutrient and sediment retention in the wetland and can serve as a foundation for the development of similar models applicable at larger scales.
Direct questions and requests to the Principle Investigator.
The purposes of the project are to: 1) hydrologically reconnect a diked wetland to Lake Erie to restore coastal wetland function and native species habitats; 2) implement a short- and long-term monitoring program to characterize response of biotic and abiotic ecosystem elements, especially those relating to Beneficial Use Impairments (e.g., phosphorus retention) after restoration actions, and 3) communicate project results to researchers, managers, policy makers, and the general public to ensure that outcomes of the project can: a) guide future management and restoration efforts in western Lake Erie and throughout the Great Lakes basin; b) contribute to landscape-level efforts to improve ecosystem resiliency to stressors, and c) support implementation of sustainable and adaptive management strategies.