Six years later… New population monitoring data for an endemic and endangered coastal lizard species in Brazil

Abstract

Habitat degradation is considered a huge threat to biodiversity and could become even worse with climate change. If the current situation of Atlantic Forest is not good, then the Restinga ecosystems are even worse due to the high urbanization rate. Glaucomastix littoralis, a lizard species that is endemic and restricted to Restinga areas of Rio de Janeiro State- Brazil, has become even more threatened in the last 10 years mainly due to degradation of physical vegetation structure, since it is closely related to local vegetation. Fieldwork was carried out in the Restingas of Grussai, Jurubatiba, Marica and Marambaia. We performed two density sampling methods and analyzed the degradation index and loss of substrate in each area aiming to compare and monitor the results over a 13 year sampling period. According to method I, the population density of G.littoralis presented smaller variation between 2013 and 2018, as did the amount of degradation elements, while method II showed an increase in population density. The Jurubatiba Restinga was considered the best area for maintaining this species, while Marambaia is the area where the species are most at risk. The density sampling methods utilized were efficient for understanding the lizards’ responses to small-scale and large-scale degradation items. Monitoring the only four populations of this species and the preservation status of each Restinga where it occurs is essential for tracking the species’ density variations and for preserving it.