Development of dispersionary and anti-predator behaviour in young wild rabbits (Oryctolagus cuniculus (L.)) in sand dunes
Patterns of dispersion of young wild rabbits, in relation to conspecifics and burrows, were studied in a wild population of young rabbits in a sand dune habitat. In general, no significant age-related changes in mean nearest-neighbour distances were observed. Although littermates were closer than expected by chance, young rabbits spent more time on the surface with non-related young than with a mixture of littermates and non-littermates. Nearest-adult distances were very close to those expected by chance. Unrelated young tended to diverge from each other when closer than 1m, but this effect was not observed at greater nearest-young distances. More divergent movements than convergent ones were also observed in the case of different nearest-adult distances. It is suggested that for young rabbits in a sand dune population kin-group cohesion is not an important characteristic of the social system. Young rabbits did not show a close association with their original burrow; from the first week of life on the surface, they used different burrows. No significant age-related changes in the mean distance from different kinds of burrows were observed. The mean distance from the nearest burrow remained always under 3m, but this may have been due largely to the high density of burrows. The apparent freedom of movements of young rabbits between different burrows may be related to the social system of the adults. The frequency of sitting alert increased with age in 1984, but it decreased the following year and predictions about the relationship between vigilance and social behaviour were not confirmed. On the other hand, lying and feeding remained nearly constant with age, but the frequency of lying was higher at less than 1m from the burrow than at greater distances. Both maturation/learning processes and external factors appeared to influence the development of behaviour of young rabbits. The effects of age and experience on anti-predator responses were followed using different models of predators. Baby rabbits showed greater alertness than older individuals. Experienced rabbits, more than inexperienced ones, showed different responses to different stimuli. It is suggested that some form of learning improves the quality of anti-predator responses.