Behaviour is the baseline of all animal activities and is continuously modified by cues and clues coming from their environment. Individuals are programmed to survive, mate, and optimize their fitness, and to accomplish these tasks they interact with conspecifics, other organisms, and other elements of their environment. Our project, merges animal behaviour, sensory ecology, and cognition, and aims at studying those cues and clues influencing seabirds’ behaviour. Our project essentially focuses on two main chapters, mate choice in seabirds, and cognitive abilities in scavenging/predators birds. We want to investigate the complex mate choice mechanisms in petrels and penguins, which communication channels are used, and which information are broadcasted to support the choice. We will not neglect any sensory channel considering vocal, chemical and visual communication. In addition, we aim at understanding the mechanisms and fitness consequences of pair coordination in petrels, and of its role as a driver of lifelong pair bond formation, eventually causing the complex mate choice behavioural process observed. Finally, we want to understand the cognitive capacities of skuas and sheathbills that live off petrels and penguins colonies. Our objective is to provide empirical data of skuas in social cognition (e.g. may skuas learn from conspecifics?), and exploring the signaling function of nest-decoration behaviour exhibited by sheathbills. Our project of fundamental science will contribute to the general knowledge of mechanisms leading the behaviour/survival/reproduction of the studied species. Correct management to decrease biodiversity-loss requires good knowledge of the ecology, behaviour and interactions of the species that we want to protect, to foresee the adaptation to changing environment.