Carnivore abundance near motorways related to prey and roadkills

Abstract

Landscape disturbance by roads may increase abundance of prey in verges 20 (i.e., strips of terrain adjacent to roadways) or create other features that can attract carnivores 21 and expose them to a higher risk of mortality by vehicle collision. We studied a system that 36 linear transects within the study area, 18 along motorways and 18 in control zones ( Fig. 1). 119We defined control zones as those with the same habitat structure and ≥4 km from habitat effect. We double-checked transects for habitat similarity; first we inspected habitat . We calculated the index value as the sum of all pellets counted in each transect. 142We estimated a carnivore abundance index as the number of scats detected in each 143 transect (Long et al. 2008 of the raw data in each transect type followed the same pattern for almost all the taxa, with 240higher mean values in motorways than in control sites (Fig. 2). Global carnivore abundance 241 increased with rabbit abundance (β = 0.103 ± 0.044, P = 0.019) and carnivore abundance was 242 higher in motorway transects than control sites (β = 0.400 ± 0.175, P = 0.022). 243The red fox showed higher abundance in motorways (β = 0.469 ± 0.197, P = 0.017) 244 but no significant response to rabbit abundance (P = 0.129; Fig. 3). The non-synanthropic 245 species showed the opposite response, with abundances positively related to rabbit abundance 246(β = 0.119 ± 0.044, P = 0.007) but no differences in abundance due to the proximity of the 247 motorway (P = 0.084; Fig. 3). 248Cascading Effects: Rabbit Abundance, Carnivore Abundance, and Roadkills 255In the analyses for the global carnivore community, roadkills were positively and numbers. For carnivores related closely to prey abundance, high prey abundance in verges 275 creates a local cascading effect that leads to carnivore roadkills. 276The increased abundance of the global carnivore community near motorways is 277 probably due to higher fox abundance in these areas, as foxes comprised almost half of the 295On the other hand, our group of non-synanthropic carnivores followed a different carnivores that prey on them will follow rabbit distribution. we controlled for by conducting DNA analysis to assess the accuracy of scat identification. 332We controlled for other potential sources of bias by choosing areas that were comparable in 333 habitat characteristics, which can affect fecal persistence and scat detectability (Long et al. are necessary to make informed management decisions that favor conservation objectives. 364Understanding wildlife responses to human-modified landscapes provides us with better 365 knowledge of the communities and identifies which processes should be the focus of our 366 conservation efforts. 367 MANAGEMENT IMPLICATIONS 368When prey are abundant near motorways, carnivores increase their abundance in those areas. 369Higher abundances of carnivores were strongly related to higher mortality by vehicles. 370Therefore, the design and management of verges could be a key aspect for conservation of 371 wil...

A review of ecological factors promoting road use by mammals

“…Iberian lynx Lynx pardinus (Garrote et al 2018) and Egyptian mongoose Herpestes ichneumon (Silva et al 2019) road kills are also associated with rabbit presence. Stone marten Martes foina , Eurasian badger Meles meles , and least weasels Mustela nivalis are detected most frequently along roads where the presence of rabbits is highest (Planillo et al 2018). American badger Taxidea taxus presence along roads was attributed to high rodent abundance (Minta & Marsh 1988), and Virginia opossums Didelphis virginiana used roadside ditches for hunting small mammals (Andersen & Fleharty 1967).…”

Habitat fragmentation and anthropogenic factors affect wildcat Felis silvestris silvestris occupancy and detectability on Mt Etna

“…from detection to retrieval or to last photo taken in case the camera malfunctioned): wildcat detections can decrease along with an increase in the effort if a trap-shy response occurs (Wegge et al 2004); 3) array (a categorical factor created for each array of traps (1-7)): given that we used seven non simultaneous arrays, we expected that all parameters of interest for the detection process could also vary by arrays, hence this detection covariate was acting as a 'random site effect' (Harihar and Pandav 2012, Tan et al 2017, Penjor et al 2018; 4) distanceMR (the straight-line distance between each camera and the closest major paved road): wildcat detections might decrease for those cameras located closer to the major roads. Indeed, it has been shown that wildcat ranging behaviour is seriously affected by the presence of such human structures (Klar et al 2009, Mata et al 2017, Planillo et al 2018; 5) RAIh (the sum of all events with humans such as bikers, hikers, forest workers and mushroom collectors): wildcat detections can be negatively influenced by persistent use of the trails by humans (Piñeiro et al 2012). Ecological covariates to model wildcat occupancy (ψ) ( Table 1) were derived from the land map 'Nature map of the Sicilian region' at the scale of 1:50 000 created in 2008 with a resolution of 1 ha.…”

Can linear transportation infrastructure verges constitute a habitat and/or a corridor for vertebrates in temperate ecosystems? A systematic review

“…It was indeed shown that some small mammals avoid going onto roads [129,130] and that several predators of small mammals are negatively affected by roads, including foxes, badgers, and snakes [19]. However, the predation release hypothesis for positive road effects on small mammals has to be clearly demonstrated [131], although the hypothesis was again supported by a recent study showing that predation rate on artificial nests was reduced up to 25 m from a highway with high traffic density [132] (but see [133]). The release from predation in roadside areas may only occur on roads with high traffic density such as highways.…”

“…Interactions between species should also be considered because the presence of a species on verges may have indirect negative effect on other species. For instance, the probability of a predator being killed on the road may be related to the presence of its prey on road verges [133,170]. We thus recommend LTI managers willing to manage verges to enhance the presence of particular species to gather information on their risk of mortality due to the LTI, their interaction with other species, and their overall population status in the area, that is, to adopt ecosystem and landscape levels approaches.…”