The Ethiopian wolf is a social animal, living in family groups containing up to 20 adults (individuals older than one year), though packs of six wolves are more common. Packs are formed by dispersing males and a few females, which with the exception of the breeding female, are reproductively suppressed. Each pack has a well-established hierarchy, with dominance and subordination displays being common. Upon dying, a breeding female can be replaced by a resident daughter, though this increases the risk of inbreeding. Such a risk is sometimes circumvented by multiple paternity and extra-pack matings. The dispersal of wolves from their packs is largely restricted by the scarcity of unoccupied habitat.
These packs live in communal territories, which encompass 6 km2 (2.3 sq mi) of land on average. In areas with little food, the species lives in pairs, sometimes accompanied by pups, and defends larger territories averaging 13.4 km2 (5.2 sq mi). In the absence of disease, Ethiopian wolf territories are largely stable, but packs can expand whenever the opportunity arises, such as when another pack disappears. The size of each territory correlates with the abundance of rodents, the number of wolves in a pack, and the survival of pups. Ethiopian wolves rest together in the open at night, and congregate for greetings and border patrols at dawn, noon, and evening. They may shelter from rain under overhanging rocks and behind boulders. The species never sleeps in dens, and only uses them for nursing pups. When patrolling their territories, Ethiopian wolves regularly scent-mark, and interact aggressively and vocally with other packs. Such confrontations typically end with the retreat of the smaller group.