Rowan's work aims to support society in making well-informed decisions regarding interactions with marine ecosystems, to meet current needs without compromising those of future generations. To do this, he focuses his research on disentangling what drives ecosystem structure and function and engages at the interface between science, decision-making and environmental stewardship. His specific research foci include theoretical ecosystem ecology, statistical and mechanistic modelling, fisheries and natural resource management, and applications of biochemical tracers to quantify trophic linkages. Much of this work has a quantitative focus, and it is grounded by several years of fieldwork above and below temperate, tropical, and southern oceans.