Assessing the influence of Humboldt penguin (Spheniscus humboldti) by excrements on the levels of trace and rare earth elements in the soil

Rare earth elements (REE) and some transition metals (e.g. Nb) are a group of chemicals that have recently been widely used in industrial processes due to the increasing demand for new technologies. As a result, these chemicals are increasingly being released into the environment, which could mean that these pollutants could modify marine and terrestrial ecosystems. Seabirds, such as penguins, can biotransport pollutants and nutrients from the sea to land through excreta. However, there is no information about the role of the Humboldt penguin (Spheniscus humboldti) in bio-transporting emerging contaminants such as REE. This study aimed to assess any possible contribution of Humboldt penguins to the geochemical composition of some terrestrial areas. Excreta samples were collected from Chañaral Island, one of the most important sites in Chile for the conservation of Humboldt penguins. The results showed that this species tends to contribute to soil enrichment with REE (Ce, La, Nd, and Pr) and Nb through excreta, as well as with carbon. More studies are needed to see the potential impacts on the soil.