Agonistic behaviour in woodchucks [Comportement agonistique chez les marmottes].

Résumé

Seven complexes of five neighbouring wood-chucks each were observed in the field between May 1959 and September 1960. Following 3 to 4 weks of observation, these animals were trapped and subjected to competitive dominance tests. Six other "aggregates" were subjected to competitive tests also. The combination of pen and field observations allowed a description of agonistic behaviour in this species. Woodchuck behaviour during the post-reproductive period (May-November) could be described as essentially ingestive, and agonistic. Animals usually lived solitarily, each animal in the population establishing dominance-subordination relationships with those animals whose home ranges overlapped or met its own.There was no evidence of territorial defence. Agonistic behaviour in the field was characterized chiefly by avoidance of dominant animals by their subordinate neighbours. The average aggressive-interaction rate in the population was about one per animal per day. This changed seasonally, increasing with the May-June period and then decreasing progressively until entrance into hibernation.