Under a perspective based on ecological gradient analysis, we found that the principal factors driving species distribution were the potential vegetation and soil type. Within the region of potential oak forests, on damped soils the omnivorous or the seed eating species found better conditions than the zoophagous species, which instead found better conditions on dry soils. Within the region of the potential Mediterranean vegetation, feeding strategy is more uniformly characterised by generalist predators species, with no apparent influence from the soil type.