Diversity of fungi attached to birds corresponds to the habitat ecologies of their avian dispersal vectors.

Background and aims: Animal-mediated transport of propagules is an important aspect of dispersal in many organisms, but severely understudied in fungi. Birds appear as natural dispersal vectors for many fungi, as they are often both mobile and migratory, potentially providing directed transport of fungal propagules to suitable sites for establishment. However, information of which fungal taxa are transported by which bird vectors is lacking.

Methods: By using environmental DNA (eDNA) metabarcoding of feather and feet swabs collected from bird species with two contrasting habitat ecologies (European Robin Erithacus rubecula and Goldcrest Regulus regulus), we identify and compare fungal diversity attached to these birds.

Key results: We identified over 600 fungal taxa attached to and potentially transported by the birds. Differences in the fungal assemblages of the two bird species corresponded with species-specific patterns in the natural histories of transported fungi and the bird vector.

Conclusions: Our findings show that bird-mediated transport can be important for a variety of fungal taxa, especially at medium to long transport distances. Taxa particularly affected includes plant pathogens, saprobic macrofungi and sorediate macrolichens, especially those with specific habitat requirements.