The effect of Mediterranean dehesa management on lizard distribution and conservation

Abstract

Management of dehesas (i.e. oak woodland pastures) creates a patchwork of sectors that differ in their structure and composition of understorey vegetation. We analysed whether different management techniques affect the populations of several species of lizards ( Podarcis hispanica, Psammodromus algirus, Psammodromus hispanicus, Acanthodactylus erythrurus, and Lacerta lepida). Multivariate analyses showed that lizards preferentially used forested areas with scrub while they avoided open herbaceous areas. The abundance of lizards increased when the understorey bushy vegetation increased. In contrast, grasslands or cereal fields were scarcely occupied even if holm oak trees ( Quercus ilex) were present, apparently because low shrubs were scarce here. Therefore, some of the traditional management practices of dehesas may negatively affect lizard populations. These conclusions could have wider implications for the design of wildlife reserves within dehesas, which has been previously based on the umbrella species concept (e.g. some dehesas are managed for imperial eagle Aquila adalberti conservation), without considering habitat requirements of other representative animal groups.