Mesocarnivore Distribution along Gradients of Anthropogenic Disturbance in Mediterranean Landscapes

Abstract

Wildfires are important sources of landscape change in Mediterranean environments, creating large patches of low-growth natural habitats (i.e., scrublands) inside protected areas, whereas woodland patches remain mostly near well protected human settlements. Landscape patterns resulting from these gradients influence habitat suitability for mesocarnivores regarding food and shelter. In winter and summer 2019, we sampled 16 independent line-transects with four camera traps each (64 cameras overall), covering the main habitats of the study area (woodlands, scrublands, and crops). Cameras were baited to compensate for the low detectability of target species, and mesocarnivore contacts were analysed by means of GLMMs and occupancy models. Our results showed a positive and stronger association of wild species with woodland habitats, despite the low proportion of habitat available, higher presence of competitors (other mesocarnivores), and potential predators (human pets, i.e., dogs), and low natural prey availability than in scrubland (i.e., small mammals). However, mesocarnivores will find protection against predators and resting sites in forests as well as other food opportunities in crops and urban areas, despite the possible interference with humans and their pets. Potential cascading effects linked to ecological roles of Mediterranean mesocarnivores on the succession of Mediterranean landscapes would imply longer-term effects of human disturbance on landscape trends.

Indirect Human Influences in Fear Landscapes: Varying Effects of Moonlight on Small Mammal Activity along Man-Made Gradients of Vegetation Structure

“…The vegetation structure of habitats obviously influences the quantity of lunar illumination that reaches the vegetation layers that small mammals inhabit. Fine-scale changes in the vegetation structure at this level alter the perception of fear by small mammals, and these responses seem to depend on the abundance of predators [ 13 , 21 ]. The perception of risk seems to be higher in open areas such as scrublands [ 16 ], where the proportion of lunar illumination reaching the lower vegetation levels is much greater than in forests.…”

“…We estimated the vegetation structure of sampling plots by ALS LiDAR [ 20 ] obtained from the Institut Cartogràfic i Geològic de Catalunya (flights 2016–2017). LiDAR provides maps of the three-dimensional structure of vegetation, even for complex and heterogeneous habitats (forests with several vegetation strata) [ 20 , 21 ], showing similar or better performance than visual field-based techniques [ 25 , 26 ] The extraction of the LiDAR data was performed on circular plots with a radius of 53 m (8834 m 2 ) centred on each plot, being equivalent to the square of 75 m × 75 m delimited by the four corners of the SEMICE sampling plots. LiDAR point clouds were obtained with a point density between 1 and 4.28 points/m 2 .…”

“…These changes are causing the conversion of open-land uses (crops, grasslands, scrub) to forest habitats, following a natural rewilding process (e.g., a passive restoration of natural ecosystems through ecological succession [ 19 ]). Gradients of vegetation structure complexity are interesting grounds for studying small mammal population responses, due to the strong habitat preferences shown by both common small mammal species and their predators [ 20 , 21 ]. Vegetation gradients are expected to produce significant changes in abundance and activity that can be modulated by perceived predation risk.…”

Assessing the Effects of Landscape Change on the Occupancy Dynamics of the Greater White-Toothed Shrew Crocidura russula

“…Being aware of the low sample size, the models predicted a decline of species occupancy due to low colonization rates caused by strong landscape change around pinewood plots. These pinewoods represent a special case of forest fragmentation caused by the opposite processes of land abandonment and wildfires [ 33 , 50 , 51 ], further influenced by strong edge effects and anthropogenic disturbances [ 52 ]. Small and isolated patches of pinewoods are almost the only representative forest habitat in the SW of the study area, probably producing a concentration of forest predators and competitors at higher rates than in continuous non-fragmented woodland of the NE.…”

Understanding the distribution and fine-scale habitat selection of mesocarnivores along a habitat quality gradient in western Himalaya

“…Their diverse nature makes them receptive to small-scale habitat alterations, and they responds more quickly than large carnivores ( Randa & Yunger, 2006 ). Thus, they serve as helpful indicator species in preserving sensitive habitats ( Kalle et al, 2013 ; Torre et al, 2022 ). Apart from being an indicator species, mesocarnivores efficiently utilise anthropogenic food sources, like garbage dumps, agricultural products, kitchen wastes and livestock carrions ( Reshamwala et al, 2018 ), due to their opportunistic behaviour and ability to adapt to modified habitats ( Rajaratnam et al, 2007 ; Lorica & Heaney, 2013 ).…”