There are two genetically divergent wild rabbit (Oryctolagus cuniculus) lineages in the Iberian Peninsula: O.c. cuniculus and O.c. algirus, which correspond to the two subspecies. The differentiation of these two subspecies has relied largely on differences in either body size or pelage, being the algirus subspecies traditionally considered of a smaller body size and darker hair. Until now, the only method available to unequivocally distinguish the two rabbit subspecies is through genetic validation. Molecular techniques have been extremely useful to determine, for example, the degree to which the subspecies gradient has been altered artificially by man, through restocking. However, these methods are neither cheap nor very swift, which often imply that hunters/conservationists manage and/or release animals without prior subspecies knowledge or validation. Therefore, the development of alternative, easier to use and equally reliable methods to determine accurately rabbit subspecies would be of great interest. The goal of this work was to provide the first contribution to the study of biometric differences between the two rabbit subspecies across wild populations from the Iberian Peninsula. We analyzed biometric data (ear and hind foot length) from rabbits belonging to 48 different Iberian populations, distributed along the subspecies gradient. Linear Mixed Models (LMM) were performed to investigate which variables (subspecies, latitude, longitude, sex, age, and the interaction subspecies*age*sex) determine the biometric differences between subspecies (site and year were included as random variables). Our results suggest that differences between the two subspecies stand out at the morphological level, being variations in ear and hind foot lengths of juvenile and adult rabbits highly dependent on the subspecies considered. Moreover, sex had an additive effect on hind foot length. Overall, the algirus subspecies presented lower ear and foot lengths. These variations could bear ecological adaptations and, hence, support potential management implications. For example, the recognition of biometrical differences between subspecies could provide a useful, swift and cheap tool to assess rabbit provenance in restockin.

Resumen del trabajo presentado a la 4th World Lagomorph Conference, celebrada en Viena (Austria) del 23 al 27 de julio de 2012.-- et al.

Peer Reviewed