A RESTORATION FRAMEWORK FOR OPTIMIZING HABITAT CONNECTIVITY IN GULF OF MAINE WATERSHEDS

Interest in restoring access to historic habitat for diadromous fish in the Gulf of Maine has led to the development of a framework for identifying and implementing barrier removal and river restoration projects. Numerous studies have identified how stream barriers disrupt ecological processes, including hydrology, passage of large woody debris and movement of organisms. Thousands of barriers exist in Maine streams and rivers, which block the passage of fish and many other aquatic and terrestrial species, as well as the natural movement of sediment and woody debris. These barriers are in the form of both dams and road-stream crossings. Recent analysis in the lower Penobscot River watershed found that barriers block access to over 70% of the historic habitat for alewife and Atlantic salmon. Using geographic information systems we have developed predictive habitat models and other datasets that are used as inputs for optimization models that maximize potential benefits from barrier removal projects while minimizing costs.