AbstractThe Antarctic terrestrial ecosystem is relatively simple and has low plant diversity. Taking into account the current effects of climate change and the exponential increase in visitors during the past 50 years, this ecosystem is very vulnerable to the arrival of non-native species. Fildes Peninsula, King George Island, is an area of high human impact due to the scientific and logistical activities that occur there making the area particularly interesting for the arrival of non-native species. In this study, we determine the spectrum of seeds arriving to the peninsula and being deposited in the topsoil. Soil samples were collected and analysed in order to identify and quantify plant material. The results indicate that there is a direct relationship between the sites where seeds were found and areas with higher levels of human activity on the peninsula. Eight species were identified, with the most common beingHypochaeris radicataandSenecio jacobaea. Seed quantification indicated that areas of high human activity are most vulnerable to the invasion and establishment of non-native species. This study is the first to demonstrate the presence of non-native seeds in the topsoil at Fildes Peninsula, Antarctica.