Understanding lichen diversity on the Antarctic Peninsula using parataxonomic units as a surrogate for species richness

Expert collection of specimens in the field and further determination of species is the best method for determining species richness. However, the relative paucity of botanists working in Antarctica makes this approach impractical for broad-scale surveys of Antarctic floral biodiversity. Lichens are the dominant macrophytes of terrestrial Antarctica and, as such, play a fundamental part of the ice-free terrestrial ecosystem. Many distinct ice-free terrestrial habitats in the Antarctic are not represented in the current network of Antarctic protected areas. However, it is difficult to identify appropriate areas for conservation because comprehensive data on distributional patterns of Antarctic flora are not available, and existing data for most Antarctic lichen species are not compiled. Consequently, cost-effective survey methods and surrogates for the prediction of species richness are needed to accelerate assessments of local biodiversity and help select areas for conservation. A combination of a photographic “citizen scientist” approach for the collection of data and the use of parataxonomic unit (PU) richness as a surrogate for species richness, might be a possible solution to effectively collect preliminary information and rapidly build databases on species diversity. We have developed a database and gathered photographic information on lichen occurrences for sites that are frequently visited by tourists. We tested the identification capabilities with a reference data set of Antarctic lichen images from the U.S. National Herbarium. We showed that all species used in this test can be detected and that, for 74% of the images, all classifiers were able to identify the genus of the specimen. Twenty-nine sites were photographically surveyed by researchers and tourists between 2009/2010 and 2011/2012 in the Antarctic Peninsula region. We estimated PU richness as a proxy for species richness for each of the 29 sites surveyed and provide two examples of potential applications. These surveys provide preliminary information for identifying areas for protection and priorities for future research.