> Abstract Aerobiological sampling was conducted year-round at three sites on Signy Island, maritime Antarctic, between December 1992 and January 1994, and during the summer at a fourth coastal site. The concentrations of keratinaceous particles were monitored. Feather fragments were the most abundant of all particle types trapped. Seal hairs were also common, particularly on the coast. Numbers of both particle types were most common in the air in summer. The Antarctic soil fungus Geomyces pannorum, which is able to utilize keratin-based substrates, was also present in aerobiological samples on Signy Island. G. pannorum was only found during early winter on the year-round sampling sites. It was more abundant during summer in the air at the coastal site, which was more heavily influenced by seals, birds and humans. Skuas were swabbed when they returned to the island early in summer. G. pannorum was recovered in culture, suggesting that these birds may act as vectors for the transport of microorganisms between Antarctica and more northern landmasses. Organic material deposited on snow was concentrated on the soil at the edge of the ice cap by melt wash, making additional keratin and other organic substrates available to soil microorganisms.