Leslie conducts research related to coastal marine ecosystems at the Darling Marine Center, UMaine's marine laboratory.

Leslie was recruited to University of Maine to provide innovative leadership and develop new research, education, and community engagement programs for the Darling Marine Center, the University of Maine’s marine laboratory. In her eight years as Director, Leslie led the DMC's first-ever strategic planning process, raised $5.2M+ to revitalize the facility's infrastructure, recruited two new faculty, and co-founded a new statewide network of public and private institutions, the Alliance for Maine's Marine Economy. Leslie also supported growth of undergraduate and graduate student programs affiliated with the DMC. Her education and mentoring activities include co-founding and leading an innovative undergraduate training program, SEA Fellows, which enables undergraduates throughout the state to gain experience and skills in applied marine research. Leslie also is a Professor in UMaine's School of Marine Sciences and leads a conservation science research group that includes graduate and undergraduate students engaged in ecology and conservation science. She and her students work closely with community and government partners on projects that draw on both natural and social science approaches to contribute to coastal community resilience in Maine, Mexico and beyond.

An international leader in marine conservation science, while on the faculty at Brown University, Heather Leslie conducted research on the ecology, policy, and management of coastal marine ecosystems. Her interests include understanding the drivers of ecological and social processes in marine systems, and how to more effectively integrate science into marine policy and management.

Leslie conducted research on coupled social-ecological marine systems and co-edited a leading text on the science and practice of marine ecosystem-based management (Island Press, 2009).