Luca Luiselli and Lorenzo Rugiero
Lorenzo Rugiero and Luca Luiselli
Massimo Capula, Lorenzo Rugiero and Luca Luiselli
Godfrey C. Akani, Godfrey C. Akani, Fabio Petrozzi, Godfrey C. Akani, Fabio Petrozzi, Lorenzo Rugiero, Godfrey C. Akani, Fabio Petrozzi, Lorenzo Rugiero, Gabriel H. Segniagbeto, Godfrey C. Akani, Fabio Petrozzi, Lorenzo Rugiero, Gabriel H. Segniagbeto and Luca Luiselli
The diet composition of rainbow lizards (Agama agama complex) populations was studied by feces analysis at eight distant places across a mega-transect in the Gulf of Guinea (West Africa), covering three countries: Togo, Benin and Nigeria. The effects of geography (= linear distance between study sites) and local conditions (using the mean annual rainfall as a proxy of the site-specific conditions) on dietary similarity of rainbow lizards were tested. Rainbow lizards were mainly insectivorous at all sites. Multivariate analyses identified four main groups of localities in terms of diet diversity indexes, with populations inhabiting forest towns tending to have less prey taxa richness than conspecifics from more arid areas, which instead had higher dietary evenness. Food niche overlap between populations was high among populations (range 0.631-0.940, ), and decreased with increases in the difference of mean annual rainfall between sites. There was no effect of the geographic distance on the similarity in diet composition between populations. A UPGMA dendrogram revealed a geographic trend in terms of presence/absence of the various prey types in the diets, with all the Nigerian study sites forming one cluster, whereas Lomé and Cotonou, two cities situated within the Dahomey Gap, being grouped apart. Overall, rainfall of the various sites seems to be more important than geographic distance for determining the taxonomic diet composition similarity of these lizards.
Silvia Del Vecchio, Lorenzo Rugiero, Luca Luiselli, Massimo Capula and Russell L. Burke
Leonardo Vignoli, Marco A. Bologna, Silvia Manzini, Lorenzo Rugiero and Luca Luiselli
Attributes of basking sites are important elements to study in management plans of threatened freshwater turtles. Here, we analyzed the basking-site characteristics of European pond turtle (Emys orbicularis) populations in a Mediterranean territory of central Italy (Tolfa Mountains, Latium). We used logistic regression and Principal Components Analysis to characterize 29 presence sites versus 61 random sites, through 16 descriptive variables recorded within a 5 m radius from the sighting/target spot. Our analyses revealed that some variables (i.e. water turbidity, presence of small coves, submerged vegetation, and emergent tree-trunks) were those that influenced most strongly the presence of turtles on potential basking sites. Maintenance of deadwood in water and preservation of submerged aquatic vegetation should be included in the management planning for this turtle species in central Italy.