Philopatry in mouflon rams during the rutting season: Psycho-ethological determinism and functional consequences

Our study of mouflon (Ovis musimon) rams in the Caroux-Espinouse massif (southern France) shows that several forms of philopatry occur. Some of the rams were sedentary, as were the ewes, up to the age of four years. Most of the rams, however, started to enlarge their home range from the age of two years. Rams of intermediate age visited their birth ranges during various periods of the year, whereas the adult males returned only during the rut. As potential mates were present on the home ranges of most of the dispersive males, it is difficult to interpret this process merely in terms of adaptation. We propose, instead, a psycho-ethological explanation, whereby the physiological disturbances intervening during the rut alter the significance of the range, the ram having to update the whole set of its sensory-motor past. This interpretation suggests that the animal has no representation of any pre-defined place, nor of any fixed aim. Rams would be able to reduce the imbalances they experience by creating a type of behaviour driven by a self-referential process, where spatial investment would outweigh any other evaluation, as an adaptative cost related to a possible inbreeding. This approach leads to reconsider the importance of spatial investment in animal's cognition and generally speaking the way an animal relates to its environment.