Informed recruitment or the importance of taking stock

Abstract

One important decision, especially for long-lived species, is where and when to start reproduction, i.e. where and when to recruit. For an informed decision on recruitment, individuals may prospect potential breeding sites and gather information on the future breeding site, hence reducing uncertainty. Recruitment may also be delayed or advanced over a range of sexually mature ages and this individual decision may influence survival costs of first reproduction, senescence patterns and ultimately lifetime reproductive success. Here we show that recruitment in the long-lived Audouin's gull is mostly informed, meaning that mainly occurs when the individual has visited the colony before. Individuals recruiting without gathering information were all young first-time breeders. Interestingly, these recruits were affected by demographic carry-over effects: first, they were much less prone to reproduce in subsequent seasons than individuals that performed informed recruitment. More strikingly, uninformed recruitment also affected survival, which was much lower for those individuals breeding without gathering information on the breeding site. This study suggests that taking stock before recruitment may be crucial for reducing environmental uncertainty and for maximising individual fitness prospects.