Riparian ecosystem configuration influences mesocarnivores presence in Mediterranean landscapes

Abstract

Riparian ecosystems are important habitat for carnivores, especially when embedded in agriculture or when found in challenging climates, such as those characteristic of the Mediterranean region. We assessed whether seasonal detection of mesocarnivores in riparian ecosystems was affected by riparian ecosystem configuration in the Mediterranean landscapes of southern Portugal. We selected riparian ecosystem areas that matched one of four configurations: (a) forest control where the riparian ecosystem was embedded in forest, (b) agriculture control where the riparian ecosystem was embedded in agriculture and does not connect to forest patches in either end, (c) short connector where stretches of riparian ecosystem <2 km long embedded in agriculture connected forest patches at both ends, and (d) long connector where stretches of riparian ecosystem >2 and <4 km long embedded in agriculture connected forest patches at both ends. We surveyed 12 areas of each configuration for signs of presence of mesocarnivores in the wet season and again in the dry season and compared them to concurrent surveys perpendicular to the riparian ecosystem using a mixed model. Corridor configuration influences carnivore detection, with short connectors (up to 2 km in length) having a positive effect on carnivore detection. Moreover, carnivores were significantly more detected along riparian ecosystems than away from them, especially within a short connector. The results also show that riparian ecosystems are being more used than forests, which is likely linked to the alternative food and cover resources that riparian ecosystems provide for mesocarnivores. Finally, we found no significant effect of seasonality. Conservation management of mesocarnivore species thus require preserving or restoring configurations such as short connectors, which are inherent to riparian ecosystems and can be used as a tool to improve connectivity.