Spatiotemporal activity of the pine marten Martes martes: insights from an island population

Behavioural interference and interspecific competition shape the spatiotemporal behaviour of carnivores, where intra-guild predation has been recorded as a strategy to limit competition. Very often, disentangling the effect of the presence of intra-guild effects from other ecological processes is challenging, if not impossible. In this work, we aimed to assess the spatiotemporal behaviour of the pine marten Martes martes in an island ecosystem without any intra-guild predation. Using an intensive camera-trap survey in the Elba Island, Italy, we estimated occupancy, detection probability and locomotor rhythms. Occupancy was higher in colder months and lowered in autumn, following opposite fluctuations of recorded human presence. The pine marten occurred much more in areas with dense vegetation (shrublands and woodlands) than in grasslands. Conversely, the detection probability remained low throughout the year, confirming the pine marten as an elusive species. Detectability decreased in proximity to paved roads and, in general, where human presence was the highest. Consistently with other studies conducted in sympatry with other carnivores or predators, in Elba Island martens showed locomotor ground activity mostly at dawn and dusk throughout the year, with an increasing diurnal locomotor activity in spring, when cubs are present. The spatiotemporal behaviour of the pine marten in Elba island did show little variation across seasons, and it was similar to those reported where potential predators were present suggesting the intra-guild predation not playing a major role in shaping the spatiotemporal activity of pine martens.