The endemic and threatened lizard Liolaemus lutzae (Squamata: Liolaemidae): current geographic distribution and areas of occurrence with estimated population densities

Abstract

ABSTRACT. Liolaemus lutzae Mertens, 1938 is a critically endangered lizard endemic to the restinga habitat of the state of Rio de Janeiro. We surveyed 25 restinga habitats in order to locate remaining populations, evaluate the status of the species, and determine the nature of local habitat degradation. We found remnant populations of L. lutzae in 18 restinga habitats of six municipalities. The conservation status of each population varied between areas: the population of Grumari, in Rio de Janeiro municipality, is the most preserved and the population of Praia do Forte, in Cabo Frio, is the most disturbed. No L. lutzae were found in Niterói municipality. The most destructive type of habitat degradation identified was the removal of beach vegetation associated with the construction of coastal roads and/or sidewalks, destruction of the vegetation due to trampling, vehicle traffic and garbage dumping. Our data revealed that generally, beach habitats under a larger number of impact sources were those with smaller population sizes of L. lutzae. We consider that the most effective conservation measure for L. lutzae is the strict protection of its habitat, with restoration of the original beach vegetation. Finally, we recommend vegetation recovery to be followed by a program of reintroduction of the species in localities where it has been eradicated.

Potential distribution of the endangered endemic lizard Liolaemus lutzae Mertens, 1938 (Liolaemidae): are there other suitable areas for a geographically restricted species?

“…We used the occurrence records of Liolaemus lutzae from Rocha et al (2009a) (Table 1, Figure 1), excluding the population from Praia das Neves (state of Espírito Santo), due to this population resulting from an experimental introduction in the area and not within the original species distribution (see Soares and Araújo, 2008). Table 1.…”

“…Modified from Rocha et al (2009a To create the potential distribution model, we used the software MaxEnt 3.2.3. Despite the availability of different methods for potential distribution modelling, some studies have shown the Maximum Entropy as one of the best performing algorithms (e.g., Elith et al, 2006;Costa et al, 2010;Giovanelli et al, 2010).…”

“…Variables with high correlation (up to 75%) were excluded from the analysis. The Jacknife test was performed to Rocha et al (2009a).…”

“…Different techniques for characterising the geographical distribution of species relate the occurrence records of species with environmental data, and have been widely applied in different geographical scales (Guisan and Thuiller, 2005;Phillips et al, 2006;a Pearson et al, 2007). Applicability of such techniques include easier detection of unknown distribution areas for a species having few distributional records (Bourg et al, 2005), potential impacts of environmental changes on organisms (e.g., Rocha et al, 2009a;Sinervo et al, 2010), the support when planning conservation policies (e.g., Araújo and Williams, 2000) and to preview potential expansion in distribution of invasive alien species (e.g., Thuiller et al, 2005;Rödder et al, 2008). Species distribution modelling is commonly based substantially on climatic variables that have strong association with broad-scale geographic patterns of species richness (Hawkins et al, 2003;Buckley and Jetz, 2007).…”

“…Its distribution is markedly narrow and comprises from Restinga da Marambaia (23°04'S, 43°52'W) to Cabo Frio (22°51'S, 41°59'W), inserted in the Atlantic Rainforest domain (for details on 'restinga' environment, see Araujo and Henriques, 1984;Suguio and Tessler, 1984;Pereira and Araújo, 2000). In these areas, L. lutzae is mainly found in a thin strip of approximately 50 to 100 m wide of beach vegetation (Vanzolini and Ab'Saber, 1968;Rocha, 1991;Rocha et al, 2009a) where males and females share the relatively small area of habitat for their ecological tasks such as thermoregulation (Rocha, 1995), space use (Rocha, 1999) and feeding activities (Rocha, 1989). This species is currently considered to be threatened with extinction even in State level (Governmental Decree from 5 june 1998; Bergallo et al, 1998), as in federal level (Brasil, 2003) and global level (IUCN, 2012), as result of the intensive and extensive destruction of restinga habitats (Rocha et al, 2007).…”