Do population parameters influence the role of seabird colonies as secondary pollutants source? A case study for Antarctic ecosystems

Pollutants in Antarctic ecosystems are largely attributed to long range atmospheric transport. However, previous studies confirmed seabird colonies as relevant secondary sources of organic and inorganic pollutants. When comparing these data, higher trophic level seabird colonies, small and sparse, did not influence results as strongly as lower trophic level birds large dense colonies. Thus, we cross examined results of stable isotopes and pollutants from lichens, moss and soil samples from Antarctic seabird colonies with their data for population parameters to understand how these variables influence each other. Results showed colonies clearly supplying As, Cd, Hg, Se, Zn, HCB and PCBs and corroborated other local sources. Penguin colonies were the most important pollutants sources hereby studied due to their sheer size and also their recent relative growth. Finally, results suggest climate change should likely increase the concentration of contaminants and the overall burden trapped in Antarctic terrestrial ecosystems. (AU)