Analyzing the Effects of Barriers on Fish Movement

In the United States, dams have been a ubiquitous feature on rivers for the past two hundred years. Around 3,000 of the 80,000 dams in the United States are located in Massachusetts, and these dams have been used for flood control, hydropower, water for citizen use, and to power mills. With many of Massachusetts' dams built in the mid-1800s and earlier, and approximately 90% of them no longer functioning in their intended capacity, more focus has been turned to their removal; dam removal is beneficial for human safety, river ecology, and fish movement. Diadromous fish require long movements along river corridors to complete their life cycle, while non-anadromous fish depend on river corridors to make small-scale movements that are important for population persistence. For my thesis, I am analyzing the impact of barriers on slimy sculpin movement by use of the sib-split method, which uses genetics to identify the presence of full siblings on either side of a barrier, and from there make inferences about movement patterns. This study aims to increase the understanding of non-anadromous fishes' ability to pass through river impoundments, through the analysis of the effects of dam removal on slimy sculpin movement and determination of the effects of location on movement. My thesis will add to the ecological understanding of the effects of barriers on connectivity and movement, which may influence management decisions and assist advocates in pushing for dam removal to restore river flows and allow for fish movement and population persistence.