Crepuscular and small but not evolutionary unique species are the reptiles less affected by roadkill in Europe

Abstract

We extensively reviewed scientific literature and extracted a large dataset with roadkill events for reptile species. We examined 300 articles from 33 European countries, gathering 1688 records of reptiles killed by vehicle traffic. A total of 125 taxa were found documented as roadkill (100 native and 25 exotic species). We calculated each species' occurrence frequency within the database (henceforth ‘relative roadkill frequency'). The relative roadkill of species was strongly and significantly correlated when comparing the whole dataset and the subset of systematic studies. We modelled the inter‐specific variation in relative roadkill frequency across the European reptilian phylogeny concerning species traits, evolutionary uniqueness, and distribution range using a phylogenetic generalized least squares (PGLS) model. Overall, reptile casualties are more pronounced for more closely related species. However, the relative roadkill frequency was unrelated to the level of evolutionary distinctiveness of European reptiles. Additionally, relative roadkill frequency was not correlated to the distribution range but was positively correlated with the species' body mass. The reptiles more frequently cited as road casualties were overall relatively large species: Montpellier snake Malpolon monspessulanus, European grass snake Natrix natrix, and Caspian whipsnake Dolichophis caspius. Additionally, more active species during the crepuscular hours were less affected by roadkill. From a conservation point of view, our results suggest that roadkill frequency is not more significant for evolutionary, more unique reptiles than for other species in Europe, while at the same time, widely distributed species are not the main target of roadkill events. Then, the main causes of roadkill in reptiles must be associated with other factors, such as behavioural traits or density of populations, rather than simply the size of their distribution range.Keywords: evolutionary uniqueness, phylogenetic signal, reptile species, roadkill incidence, wildlife conservation