The Study of Flora and Its Relationship with the Breeding Grounds of Black-Tailed Gulls on Hongdo Island (Tongyeong, Gyeongnam)

Hongdo, located in Hansan-myeon, Tongyeong-si, Gyeongnam, is the largest black-tailed gull breeding ground on the Korean Peninsula and is managed as a natural monument. The plants distributed in Hongdo are not only used as nesting materials during the breeding season of black-tailed gulls but also as important hiding places for juveniles. This study aimed to identify the flora, characteristics, and changes in Hongdo, determine the relevance of the results to black-tailed gull breeding grounds, and use the results as basic data for the conservation of biological resources in the national park special protection area. Ten field surveys were conducted from May 2019 to May 2023. As a result of this survey, a total of 26 taxa were identified: 17 families, 25 genera, 21 species, and 5 varieties of indigenous vascular plants. A total of 26 taxa were surveyed: one family and one species of pter- idophytes, three families, eight species, two varieties, and 10 taxa of gymnosperms, and 13 families, 12 species, three varieties, and 15 taxa of angiosperms. In Hongdo, no endangered wild species and plants were classified as endangered by the IUCN, and no endemic species in the Korean Peninsula were confirmed.