Wetland Restoration in Typha-Dominated Braddock Bay of Lake Ontario

Abstract

The barrier beach at the Braddock Bay wetland on Lake Ontario was lost to erosion. Without the protective barrier, the area of vegetated wetland was reduced by wave attack. Lake-level regulation implemented in 1960 resulted in cattail (primarily hybrid Typha × glauca), invasion and loss of sedge-grass meadow habitat. As part of the Rochester Embayment Great Lakes Area of Concern, Braddock Bay was targeted for restoration by the U.S. Army Corps of Engineers. The plan included reducing coverage by cattails, construction of channels and potholes to improve wildlife access to the wetland, creation of spoil mounds along the channels to discourage growth of cattail while supporting the growth of sedge-grass meadow species, re-creation of the barrier beach, and construction of new emergent marsh. We collected vegetation data for three years following the 2016 construction activities. Post-restoration results showed that cattail cover decreased greatly across years in the cattail treatment areas, decreased in lower elevation constructed habitats, and gradually increased in higher elevation habitats. Opening of the canopy resulted in increased floating and submersed species, and constructed mounds hosted wet meadow species. Site-level weighted mean C is recommended for future data analyses, rather than FQAI or mean C, because it has no observed influence from species richness. Restoration results were affected by high lake levels in 2017, identified problems in seeding and planting, and meeting construction plans for some channel and pothole depths and mound elevations. Pre-restoration soil surveys are recommended to reduce construction problems, and adaptive management should include invasive species control.