Study of territorial behaviour and stress for the improvement of European wild rabbit restocking programs

Abstract

The European rabbit (Oryctolagus cuniculus L.) is a keystone species that is native to the Iberian Peninsula and whose populations have undergone a dramatic decline in abundance in their natural ranges throughout the second half of the 20th century. The economic and ecological importance of the wild rabbit has now led to the need to perform management actions aimed at boosting the remaining populations and establishing new ones, particularly in Mediterranean areas. Restocking actions are one of the handiest management tools, and scientific research whose objective is to define and solve the major methodological problems is abundant in literature. However, the majority of research has focused on factors which are extrinsic to wild rabbits, such as predation, diseases and habitat, while neglecting other factors that are intrinsic to wild rabbit biology. The principal aim of this PhD thesis is to improve the efficiency of wild rabbit restocking programs by taking into account intrinsic aspects of rabbit biology such as social behaviour and stress. In order to do so, I have performed five experiments whose intention has been to test Fecal Near Infrared Reflectance Spectroscopy and indigestible faecal markers as cheap, easy, user-friendly and non-invasive tools by which territorial marking by wild rabbits can be studied; I have also measured restocked wild rabbit populations’ responsiveness to acute stressors in a non-invasive manner as a predictor of population growth during the breeding season; I have additionally studied the density-dependence phenomenon inside wild rabbit restocking plots, with the aim of providing a better management of these plots and improving their efficiency as extensive breeding sites; and finally, I have performed a supplementary experiment with wild-type rats with the intention of attaining a better understanding of the relationship between physiological stress and territorial behaviour. The first four chapters are framed...