The UNESCO Cape Horn Biosphere Reserve, Chile, has been identified as one of the 24 most pristine ecoregions in the world. Located at the southern-most tip of the South American continent, terrestrial areas south of 47 oS no replicates in the world, and contains many unique biotic communities. In recent years Horn Island has become a major tourist attraction, with over 10000 tourists visiting annually. While boardwalks protect the fragile ecosystems from immediate damage, tourists may carry with them seeds of non-native species. Determining a baseline of species diversity in the archipelago was conducted in 1980 and 2003, before tourism was at the current levels, to determine if invasive species were present on Horn Island. In January 2019 an expedition was taken to Horn Island to assess the impact of tourism. We created an herbarium collection for vascular flora to determine if any invasive species had colonized the island. The collection was focused around the area closest to the areas visited by tourists, particularly close to elevated boardwalk, as it was deemed the most likely area for invasive species to first present themselves.
Results/Conclusions
The collected herbarium consists of 61 specimens, from 25 different families. No non-native species were identified in the field, or identified after collection. The presence of invasive species is of particular concern on Horn Island due to the uniqueness of the biotic communities, and the lack of world-wide replicates. Non-native species that become invasive species have been shown in many previous studies to have significant impacts on many ecological variables, as well effecting the evolution of native species. Continual monitoring should be conducted on the island, particularly in the habitats adjacent to the boardwalk to ensure that any non-native species are identified rapidly, and steps may be taken to remove them from the island.