Improved local inventory and regional contextualization for anuran (Amphibia) diversity assessment at an endangered habitat in southeastern Brazil

Amphibians are suffering population declines around the world and the main causes are related to human activities, especially those involving direct habitat destruction. On the other hand, we are far behind in our knowledge of species distribution, natural history and even taxonomy. Some areas are under high levels of threat due to their economic relevance, as is the case for the Quadrilátero Ferrífero, a biodiverse area that is rich in iron deposits in the southernmost highlands of the Espinhaço Mountain Range, in southeastern Brazil. Using four lakes in the Quadrilátero Ferrífero as an example, we aimed to employ two approaches that we believe can improve short-term species inventories such as those needed to meet legal requirements for potentially impacting enterprises (e.g. mining). These approaches were (1) combination of tadpole and adult frog inventories and (2) regional contextualization of local species assemblages. We found adult frog and tadpole sampling to be complementary and representative of all anuran life stages. We also found the studied habitats to be considerably different from all other sampled habitats in the Quadrilátero Ferrífero (which also differed substantially among them). This high spatial heterogeneity could not be explained by geographic distance, even accounting for the effects of different types of bodies of water and sampling methods among sites. These findings have important conservation implications. Thorough inventories including both adult and tadpole stages are recommended for any new potentially destructive enterprise to be implemented in the Quadrilátero Ferrífero, because endemic species and unique anuran assemblages are likely to be lost.