Social Behaviour, Vocalization and Conservation of Narwhals

摘要

LIVING IN GROUPS IS HIGHLY BENEFICIAL FOR INDIVIDUALS of social species. Group living improves resource acquisition (Creel and Creel, 1995), vigilance, and defence against predators (e.g., Bertram, 1980), as well as enhancing the care of the offspring (Clutton-Brock, 2002). In some species, such as African elephants (Loxodonta africana; Wittemyer et al., 2005) and resident killer whales ( Orcinus orca; Bigg et al., 1990), individuals form permanent groups that they keep for their entire life. Groups can differ in behaviours that affect their fitness, such as their food preferences and hunting techniques, or in the use of tools (Whiten et al., 1999). In some groups, older individuals possess ecological knowledge that they share only with the rest of their group, which gives fitness advantages to the members of that group (Payne, 2003). Thus, group membership may ultimately affect individual survival.