Individual consistency in the non-breeding behavior of a long-distance migrant seabird, the Grey Petrel Procellaria cinerea

International audienceThere is growing interest in the consistency of individual differences in animal behavior as it relates to life history traits and fitness. Despitethe relatively large number of studies investigating repeatable behaviors, studies have only recently investigated repeatability in foraging ormigratory behaviors, and this has seldom been explored between years. We examined the individual consistency in foraging behavior of theGrey Petrel Procellaria cinerea, a pelagic long-distance migrant seabird. We analyzed how foraging, activity, and migratory patterns wererepeatable across different seasons. We used tracking data to monitor the migratory movements and behavior of individuals during the nonbreedingperiod over five years. Despite the small sample size, we found that there was a relatively high individual consistency in winteringstrategies across years, with birds displaying high fidelity to their non-breeding destinations during consecutive years. Activity parameters,date of departure of inward migration, duration of migration, and duration spent in non-breeding areas were repeatable as well. The durationof the non-breeding period was the most repeatable, reflecting consistent departure times and, to a lesser extent, consistent arrival times.A high overall repeatability was seen in the timing of return migration. With respect to sex, males tended to be more consistent in theirmigration strategy (i.e., timing of migration, time spent in non-breeding areas) than females. Although conditions during the Holocene havegenerally been stable in the Southern Ocean, species lacking variability in migratory traits are probably at a considerable disadvantage interms of their capacity to respond to the rapid environmental changes currently underway