Arthropods as bioindicators of the red fox foraging activity in a Mediterranean beach-dune system

Remains of invertebrates have been observed in the faeces of foxes found in the protected littoral area of Burano (GR, Italy). From knowledge of the eco-ethology of arthropods that live in this environment, an attempt was made to assess the spatial and temporal strategies of the red fox. A total of 525 faeces were analysed. Monthly samplings were made along two transects for an entire year. At the same time, standard trapping methods were used to collect arthropods that could represent foxʹs possible prey. During winter remains of plants and vertebrates were the main categories found in the faeces, whereas in the other seasons invertebrates, and in particular Coleoptera, principally occurred in the faeces. Taxa belonging to other environments and items scavenged from waste ground were not found. Through the zonation and activity patterns of the most abundant invertebrate categories, a seasonal change in the foxʹs foraging strategy was assessed. Foxes were active in different zones and hours of the day, according to the season, preying on large invertebrates during their period of surface activity (diurnal–nocturnal) or smelling them under beach debris (diurnal and seasonal resting sites). The results confirm the great behavioural plasticity of the fox which prefers to exploit food resources found in an undisturbed environment, modulating its feeding both in space and in time, rather than searching for food outside the protected area.