Plant invasion: Another threat to the São Paulo Marsh Antwren (<i>Formicivora paludicola</i>), a species on the verge of extinction

<div><p>During the past 100 years in densely populated south-eastern Brazil, wetlands have been severely transformed due to urbanization, agriculture and mining. The recently discovered São Paulo Marsh Antwren (<i>Formicivora paludicola</i>) is endemic to these wetlands, and is listed as “Critically Endangered” by the IUCN. The species is only found in an area of 1.42 km², it has a sparse and fragmented distribution, low dispersal capacity, and has probably lost around 300 km² of habitat in the past 100 years. Furthermore, very little is known about <i>F</i>. <i>paludicola</i> natural history, and so it is difficult to construct a robust conservation plan. Using Kernel home range estimations and the Adjusted-SD/Torus Shift test (a novel tool for animal-habitat association studies), we showed that the species avoids patches of the alien invasive ginger lily (<i>Hedychium coronarium</i>). Given the high density of their population (3.6 mature individuals/ha), <i>F</i>. <i>paludicola</i> could thrive in relatively small areas of suitable wetlands protected from human occupation and water contamination, however special attention should be paid to biological invasions, which may represent a serious threat to the remaining populations. Protecting a few small wetlands used by <i>F</i>. <i>paludicola</i> would be an important step towards general conservation and restoration of Atlantic Forest wetlands and its endemic endangered species.</p>