Status of Marine Debris Damage to Adult and Young Black-Tailed Gulls (Larus crassirostris) in Their Breeding Colonies in South Korea

Abstract

Marine debris from fishing-related paraphernalia poses a threat to the survival of marine organisms, especially seabirds. Although the detrimental effects of marine debris on seabirds have been documented, studies on the extent of damage inflicted by marine debris on the seabird breeding population are scarce. Here, marine debris ingestion and entanglement damage to black-tailed gulls (Larus crassirostris) residing in South Korea were quantified. The five breeding colonies of black-tailed gulls were visited, and the frequency of ingestion and entanglement damage in adults and young were recorded. A total of 25 cases of marine debris damage were confirmed. As a result, damage by marine debris to gulls varied depending on breeding colonies. More adults suffered from entanglement damage than the young, and their most damaged parts were usually their legs. Fishing lines and hooks caused the most damage. We suggest that marine debris damage acquired in breeding colonies could affect breeding success.