Endangered mussels and dams: navigating the complex waters of river restoration and mussel mitigation
Beth Swartz, Maine Department of Inland Fisheries & Wildlife, Bangor, Maine



Abstract:

During the past 15 years, Maine has experienced a steady pulse of large and small dam removals, primarily as a means to improve access and habitat for anadromous fish. These river restoration projects often overlap with populations of Maine's state-listed freshwater mussel species: the brook floater (Alasmidonta varicosa), yellow lampmussel (Lampsilis cariosa) and tidewater mucket (Leptodea ochracea). While dam removal is unquestionably good for the brook floater, impoundments in Maine provide suitable and sometimes excellent habitat for the yellow lampmussel and tidewater mucket. Consequently, while removing dams provides a multitude of benefits to riverine species, including many freshwater mollusks, it also poses a potential threat to some of the state's best populations of these two rare species. Because the Maine Endangered Species Act prohibits take of a listed species, dam removal project applicants must work with MDIFW to determine if rare species are present in the project area and, if so, develop a plan to minimize mortality.
This is typically done through an Incidental Take Plan (ITP) process. Since Maine's first large scale dam removal in 1999, the ITP process and the methods used to survey, recover, relocate and post-monitor mussels threatened by dam removal have continually evolved as trial and error, and increasing experience nudge the bar higher with each new project.

This talk focuses on Maine's experience with designing and implementing recovery and mitigation plans for rare mussels affected by some of the country's most historic dam removal projects. It begins with an overview of the regulatory nexus that requires mussels to be considered in project plans; recounts the history and evolution of current protocols using specific dam removals and their incidental take plans as examples; and offers an honest assessment of mistakes made, lessons learned, persistent shortcomings, and nagging unanswered questions.

Biography:

Beth Swartz is a Wildlife Biologist with the Reptile, Amphibian and Invertebrate Group of the Maine Department of Inland Fisheries and Wildlife in Bangor, Maine. She has been with the agency for 27 years, where one of her responsibilities is to serve as lead biologist on the conservation of Maine's freshwater mussels. In that role, Beth coordinates all aspects of the Department's mussel conservation efforts from surveys and status assessments to environmental review and research collaboration. Over the past 15 years, she has been intimately involved with organizing recovery and relocation efforts for at least nine major dam removal and repair projects where state-listed species were affected.