Carry-over effects, whereby events in one season have consequences in subsequent
seasons, have important demographic implications. Although most studies examine carry-over
effects across 2 seasons in single populations, the effects may persist beyond the following season
and vary across a species’ range. To assess potential carry-over effects across the annual cycle and
among populations, we deployed geolocation loggers on black-legged kittiwakes Rissa tridactyla
at 10 colonies in the north-east Atlantic and examined relationships between the timing and
destination of migratory movements and breeding success in the year of deployment and sub –
sequent season. Both successful and unsuccessful breeders wintered primarily in the north-west
Atlantic. Breeding success affected the timing of migration, whereby unsuccessful breeders
departed the colony earlier, arrived at the post-breeding and main wintering areas sooner, and
departed later the following spring. However, these patterns were only apparent in colonies in the
south-west of the study region. Furthermore, the effect of breeding success was stronger on
migration timing in the first part of the winter than later. Timing of migratory movements was
weakly linked to subsequent breeding success, and there was no detectable association between
breeding success in the 2 seasons. Our results indicate temporal structure and spatial hetero –
geneity in the strength of seasonal interactions among kittiwakes breeding in the north-east
Atlantic. Variable fitness consequences for individuals from different colonies could have important
implications for population processes across the species’ range and suggest that the spatiotemporal
dynamics of carry-over effects warrant further study.
Seasonal interactions · Migration · Reproduction · Life-history strategies ·
Geolocation · Black-legged kittiwake · Rissa tridactyla · North Atlantic
