ИСТИНА

While urban populations of European Herring Gulls Larus argentatus are increasing, rural populations are declining over wide parts of the species’ breeding range. Herring Gulls are generalists with potentially a high degree of individual specification and are more linked to human activities than most other seabirds. However, we have a limited understanding of how individuals may repeat or adapt their strategies across multiple years, and to what extent individual behaviour can be linked to for example breeding populations. Our study investigates these matters using geolocators retrieved from seven rural breeding sites in Iceland, Norway and in the White Sea. We quantified consistency in individual non-breeding movements, marine-terrestrial connectivity, and encounters with human sources of light at night. We found that individual strategies were to some degree linked to specific regions, e.g., birds breeding in Northern Norway spent all-year-round more time at sea, although being distributed widely during the non-breeding season. Overall, Herring Gulls exhibited a moderate degree of repeatability, with individuals generally maintaining consistent strategies across multiple non-breeding seasons. However, there were many exceptions, suggesting that individuals adapt when necessary. We show a specific case of coastal purse seine fishery in Northern Norway as an example of how Herring Gulls can adapt to where the hauls are concentrated each year.