Long-term effects of a wildfire on a lizard assemblage in the Arid Chaco forest

Abstract

The long-term (14 years) effects of a high-intensity wildfire on a lizard assemblage were studied in Chancaní Provincial Natural Park and Forest Natural Reserve (Córdoba, Argentina), by comparing a burned area with an unburned one within the protected area. Lizard diversity and abundance were measured using 25 drift-fence pitfall traps in the burned area and in a portion of the unburned forest during two summers (2006–2007 and 2007–2008). A total of 426 lizards belonging to eight species were captured. Total captures were 40% higher in the unburned area than in the burned one. From the eight species recorded, five ( Homonota fasciata, Leiosaurus paronae, Stenocercus doellojuradoi, Liolaemus chacoensis, and Teius teyou) were more abundant in the unburned area, whereas the remaining species ( Tropidurus etheridgei, Mabuya dorsivittata and Vanzosaura rubricauda) did not differ between areas. The differences observed in lizard numbers between sites may be related to fire-driven changes. A marked increase in grass cover determining the reduced availability of bare and litter-covered ground, fallen logs and dead wood, favorite microhabitats for most lizard species, is of particular significance.