Karissa was interested in physiology, behaviour, and ecology of aquatic species. Much of her work centres on how environmental changes, such as those tied to climate change and human developments, influence the metabolic physiology and energetics of aquatic species including sharks, rays, and freshwater fishes and turtles. She works on a range of projects which investigate how anthropogenic activities such as water resource development, shoreline development, fishing, and climate change affect threatened species, and how we can use this knowledge to enhance their conservation.