HABITAT CHOICE IN BREEDING SEABIRDS - WHEN TO CROSS THE INFORMATION BARRIER

The choice of breeding site is a key reproductive decision for long-li ved seabirds. Individuals pioneering new sites face unknown risks (e.g ., unfavourable predator regimes, climate), but potential breeders may derive information about reproductive opportunities from the presence of conspecifics, just as local enhancement is used to derive informat ion about local feeding conditions. We suggest here the information ba rrier hypothesis: the presence of nesting birds may furnish cues about local breeding conditions (e.g., abundant food, safe places to nest); this information advantage may deter dispersal to new habitat, even t hough good breeding sites may be available elsewhere. By settling at a n established site, individuals gain confidence that local conditions are favourable for breeding, whereas individuals pioneering new sites receive no such promise. This information barrier may entice individua ls to remain at colony sites even when breeding vacancies are few, and new recruits must queue for openings.