The reasons for the range expansion of the grey wolf, coyote and red fox

Abstract

Canidae is a species-rich, abundant, and widespread family. Several wild canid species, in particular, have shown a significant range expansion and increased abundance in the last few decades or even in the last century. The grey wolf (Canis lupus), coyote (Canis latrans), and the red fox (Vulpes vulpes) are resident on whole continents or even on multiple continents. Although canids share common behavioural and ecological characteristics, the formula of species-specific elements contributes to their success. This review investigated which factors have contributed mainly to the expansion of the grey wolf, coyote, and red fox. Analysis of the literature review shows that the grey wolf has dramatically benefitted from legal protection, reintroduction programs, and the ability to colonise areas naturally because of its particular social system, early reproduction, high fecundity, and rapid physical development. As a meso-carnivore, the coyote has shown a rapid spread after the extermination of apex predators in several regions in North America. Along with changes in land use, their high adaptability and hybridisation with wolves have all contributed to their prolonged success. The red fox has shown the largest expansion among canids even though it is a solitary species. Their morphological, reproductive and behavioural traits have facilitated their expansion to all corners of the world. Moreover, the species benefitted from human-caused changes like land conversion and the almost complete eradication of rabies in Europe. Overall, it is crucial to change management policies for grey wolves and increase control measures to regulate the three species and mitigate (potential) human-carnivore conflicts.