Peter studies the sensory physiology and behavioral ecology of marine animals with special focus on how they use and produce sound to navigate, find food, avoid predators and communicate. Primary areas of investigation include biosonar and sound production in toothed whales, kinematics of feeding and locomotion in cetaceans, and underwater communication and sound propagation in cetaceans with implications for effects of man-made noise and passive acoustic monitoring.

Peter's Marine Bioacoustics Lab at Aarhus University pursue an integrative biology approach to experiments at an organismal level with emphasis on how animals work in an evolutionary context.