Impact of invasive species on the density and body size of an insular endemic lizard (Trachylepis atlantica)

Abstract Background Invasive species have been responsible for the extinction of several species around the world. The Noronha skink is an endemic lizard from the Fernando de Noronha archipelago, Brazil, that has been suffering from habitat changes and the introduction of invasive species. Results The density of Trachylepis atlantica on the main island was 0.167 ± 0.090 individuals/m2; that on the secondary islands was 0.357 ± 0.170 individuals/m2; and that on the entire archipelago was 0.184 ± 0.109 individuals/m2. Moreover, the morphometric parameters of the Noronha skink were compared between the main island and secondary islands. The values of all parameters were higher on the secondary islands. Conclusion The occurrence of invasive species on the main island seems to be a determining factor in the density and body size of the Noronha skink.