Courtney E. Larson

Courtney E. Larson is an aquatic ecologist leading the Biomonitoring and Aquatic Studies Section in the Vermont Department of Environmental Conservation. She oversees the state’s monitoring of macroinvertebrates, fish, and habitat across Vermont’s rivers and streams. Before joining Vermont DEC, she worked at EPA’s Office of Research and Development in the Great Lakes Toxicology and Ecology Division, where she managed an environmental DNA (eDNA) laboratory and researched eDNA methods for detecting invasive species and assessing aquatic ecosystem health. Her research has included studying fish eDNA biodiversity dynamics, as well as invasive mussel, zooplankton, and protist detection. Over the course of her career, she has sampled across a wide range of habitats and geographic settings, from Great Lakes coastal waters to Puerto Rican reservoirs, giving her a broad perspective on adapting monitoring methods to different environments. Courtney holds a Ph.D. in Entomology from Michigan State University and a B.A. in Biology from Wartburg College.

Courtney is piloting environmental DNA (eDNA) biomonitoring in Vermont streams that are already part of the state’s Clean Water Act ambient biomonitoring network. She is comparing molecular results against Vermont’s extensive (>40 years) baseline data on macroinvertebrates, fish, and habitat. The project will help determine whether molecular methods can expand monitoring coverage and provide better indicators of environmental change. Beyond the laboratory work, Courtney will organize workshops bringing together social scientists, water managers, and practitioners to identify barriers to eDNA adoption and build state agency staff confidence in interpreting molecular results. The goal is to produce a framework that other states can use to incorporate eDNA into their own water quality monitoring programs, helping ensure that research investment in this technology translates into on the ground use. This project bridges Courtney’s prior research with EPA ORD on eDNA methods development to her new role within state level Clean Water Act biomonitoring implementation.