INFANTICIDE IN THE ALPINE MARMOT (MARMOTA-MARMOTA)

We report the first case of directly observed infanticide in the Alpine marmot (Marmota marmota). Moreover, previous and present observations suggest that 12 young could have been killed by infanticide in the population under study. The bodies of five of them were found with similar neck injuries. In all cases, infanticidal animals were adult males entering a territory in the absence of the resident or having taken over the territory. As in the Arctic ground squirrel, Spermophilus parryii, infanticide could have evolved in Alpine marmots as a part of the reproductive strategy of new resident males. According to ARNOLD (1990), young increase the energetic cost for related animals hibernating with them. Thus, while a rapid return to oestrus is not a realistic outcome, because it occurs only in early spring, infanticide could reduce hibernation costs for the female and increase her reproductive potential in the following year. A sexual selection hypothesis would explain infanticide in Alpine marmot.