Red foxes (Vulpes vulpes) use rabbit (Oryctolagus cuniculus) scent marks as territorial marking sites

One of the functions of chemical communication is territorial signalling. To achieve this, animals should mark their territories in a manner that increases the detectability of the marks, thereby maximising the probability that other animals detect the scent marks. In this study, we focused on the scent-marking behaviour of red foxes in relation to the abundance of their main prey, the European rabbit, in a suburban forest in Madrid, Spain. Our results reveal that foxes scent-marked more and increased the detectability of their marks in areas of higher rabbit density. It would appear that foxes defend food resources from competitors by increasing the number and the detectability of their scent marks.