The rivers and streams of the Southeastern United States are extremely diverse, containing numerous threatened and endangered species. In fact, southeastern rivers contain more at-risk freshwater fish and invertebrates than any other region of the country.
The anthropogenic fragmentation of river habitats through dams and poorly designed culverts is one of the primary threats to aquatic species in the United States. The impact of fragmentation on aquatic species generally involves loss of access to quality habitat for one or more life stages of a species. For example, dams and impassable culverts limit the ability of anadromous fish species to reach preferred spawning habitats and prevent brook trout populations from reaching thermal refuges.
Some dams provide valuable services to society including low or zero-emission hydro power, flood control, and irrigation. Many more dams, however, no longer provide the services for which they were designed (e.g. old mill dams) or are inefficient due to age or design. However, these dams still create barriers to aquatic organism passage. In addition, fish ladders have long been used to provide fish passage in situations where dam removal is not a feasible option. In many cases, these connectivity restoration projects have yielded ecological benefits such as increased anadromous fish runs, improved habitat quality for resident fish species, and expanded mussel populations. These projects have been spearheaded by state agencies, federal agencies, municipalities, NGOs, and private corporations – often working in partnership. Notably, essentially all projects have had state resource agency involvement. The majority of the funding for these projects has come from the federal government (e.g. NOAA, USFWS), but funding has also come from state and private sources. All funding sources have been impacted by recent fiscal instability and federal funding for connectivity restoration is subject to significant budget tightening and increased accountability for ecological outcomes.
To many working in the field of aquatic resource management it is apparent that given likely future constraints on availability of funds and staffing, it will be critical to be more strategic about investments in connectivity restoration projects. One approach to strategic investment is to assess the likely ecological “return on investment” associated with connectivity restoration.
The Chesapeake Fish Passage Prioritization Project assessed dams in the Chesapeake Bay Watershed based on their potential to provide ecological benefits for one or more targets (e.g. anadromous fish species or resident fish species) if removed or bypassed. Funded by the South Atlantic Landscape Conservation Cooperative (SALCC), the Southeast Aquatic Connectivity Assessment Project (SEACAP) grew out of and builds on the conceptual framework of the Chesapeake Fish Passage Prioritization Project and the Northeast Aquatic Connectivity Project.
