Prevalence of the Cladosporium cladosporioides Species Complex in the Mycelia-Like Skin Crusts of Migratory Yellow-Throated Buntings (Emberiza elegans) in Korea.

Understanding the ecological characteristics and environmental factors of migratory songbirds is essential for their conservation as well as pathogen management that may cross ecological and political boundaries. In this study, we conducted a bird trapping and banding survey and report on fungal DNA detected from birds with putative fungal skin infections. We analyzed the mycobiome of mycelia-like skin crusts of the yellow-throated bunting (Emberiza elegans), a common migratory songbird with declining population in Korea, using DNA metabarcoding targeting the internal transcribed spacer 1 (ITS1) region, the actin (ACT) gene, and the translation elongation factor 1 - α (TEF) gene. Our analysis revealed that Cladosporium was the predominant genus (~ 60% sequence reads) in fungal mycelia-like tissues on the skins of yellow-throated buntings and detected a large number of DNA sequences similar to those of species belonging to the Cladosporium cladosporioides species complex. This is the first study to report possible infection in buntings by Cladosporium, including species known to infect humans and other animals. Further research on the causal relationship between birds and fungi is needed for pathogen management and conservation of Asian songbirds along the migration flyway.