Forest passerines as a novel dispersal vector of viable bryophyte propagules

Animal dispersal influences the community structure and diversity of a wide variety of plant taxa, yet the potential effects of animal dispersal in bryophytes (hornworts, liverworts, and mosses) is poorly understood. In many communities, birds use bryophyte-abundant niche space for foraging and gathering nest material, suggesting that birds may play a role in bryophyte dispersal. As highly motile animals with long migratory routes, birds potentially provide a means for both local and long-distance bryophyte dispersal in a manner that differs greatly from passive, aerial spore dispersal. To examine this phenomenon, we collected and germinated bryophyte propagules from the legs, feet and tails of 224 birds from 34 species within a temperate forest community. In total we found 1,512 spores, and were able to germinate 242 bryophyte propagules. In addition, we provide evidence that topical (externally-carried) spore load varies by bird species and behavior. Tail feather spore abundance is h...