May’s research focuses on the interactions between physical, chemical and biological processes in river systems. Specifically, she explores hydrologic and geomorphic processes that shape river systems and the role of disturbance in aquatic ecosystems. Of particular interest are mountain stream communities, brook trout habitat, American eels and freshwater mussels. 
May received a bachelor's degree in natural resources from Humboldt State University, a master's degree in forest hydrology from Oregon State University and a doctorate in fisheries science from Oregon State University.