Relationship between Vegetation Structure and Avian Communities on Miyakejima Island, Japan, 13 Years after a Major Volcanic Eruption1

Volcanic eruptions can have significant impacts on plant and animal communities. Thus, it is important to understand the recovery process following these eruptions, particularly on isolated islands, in order to assist with biodiversity management and conservation. We studied relationships between vegetation structure and avian species composition on Miyakejima Island, Japan, where a volcanic eruption in 2000 destroyed almost half of the vegetated land. Bird species and nine vegetation variables were surveyed at 24 sampling sites from 2011 to 2014. The results showed that avian species composition mainly varied along two vegetation variables, namely plant species richness and total basal area of all tree species. Bird species were classified into four groups, that is, grassland species, widely distributed species, developing-forest species, and developed-forest species. Developed-forest species were only recorded at the sites where vegetation height was more than 10 m. The relationship between developed-forest bird abundance and vegetation height was similar to that between total basal area of all tree species and vegetation height. The restoration of mature evergreen forest is essential to conserve avian diversity on the island, and natural seed dispersal by birds plays an important role in supporting forest restoration after a major disturbance.