Coastal, River, & Wetland Restoration
- Cane Ridge Wildlife Management Area, Least Tern Habitat Restoration
Gibson County, Indiana
the challenge The Cane Ridge Wildlife Management Area (WMA) is a 474-acre property adjacent to the 3,000-acre Gibson Lake, an artificial cooling pond in Indiana. The Interior Least Tern is a migratory species that nests in shallow depressions on open sandy or gravel substrates naturally found in the Upper Mississippi Valley and Great Lakes Region. Due to the flood control and navigation efforts of the Corps of Engineers, these landforms have become increasingly stabilized and vegetated, making them unsuitable as Least Tern nesting areas. Since 1986, an expanding number of least terns have been nesting on the ash piles generated by the regional power plants, especially near Gibson Lake. However, coal and ash materials and plant operational activities do not promote successful tern reproduction in the long-term, so a more appropriate and attractive habitat area was called for.
the interdisciplinary approachA multi party, public/private partnership including the Indiana Department of Natural Resources, the Patoka River National Wildlife Management Area, the USDA Wetland Reserve Program, the Southwest Indiana Four Rivers Project, Ducks Unlimited, and the Nature Conservancy, led by the U.S. Army Corps of Engineers proposed to create artificial nesting habitat for the federally and state-listed interior least tern, and to create additional nearby wetland and bottomland riparian habitat. The Bioengineering Group performed the planning and design for the project, taking advantage of the available cooling water stream to supplement natural hydrology to exclude predators through a pond “moat”, and to recycle water to support adjacent wetlands after the nesting period. This work entailed coordinating with the various agencies and stakeholders, producing a construction drawing set including grading, planting, and seeding recommendations, and providing cost estimates and construction schedules.
the resultsThe final design is a 54-acre perched pond, surrounded by a 6-foot-high perimeter dike, with water levels maintained by flow from Gibson Lake. Islands in the pond provide nesting habitat isolated from the power plant’s activities and largely protected from predation. During the fall and winter seasons, the water level is lowered to protect the pumping equipment and provide water to 193 acres of adjacent created wetland areas, conserving water while maintaining an array of linked habitats that have succeeded in attracting many nesting pairs of endangered Least Terns for successful nesting.