The emu (Dromaius novaehollandiae) is the world’s second-largest living bird. This flightless bird is a member of the ratite family, which includes the ostrich and the cassowary. Emus are distinguished by their three-toed feet, long legs, and shaggy brown-black plumage. They are distributed widely across mainland Australia, inhabiting a variety of habitats from sclerophyll forest to savanna woodland. They are a large, terrestrial species well-adapted to surviving the continent’s often harsh and arid conditions.
The Terminology for Emu Groups
The collective noun used to describe a group of emus is a “mob.” While “mob” is the prevailing term, other collective nouns are sometimes proposed for emus, such as a “herd” or a “troop.” However, these alternatives are rarely used in general conversation or scientific literature. This term simply identifies a collection of the birds without necessarily implying a complex social structure. The word itself is highly specific to the emu in this context, answering the direct question of what to call them when seen together.
Social Dynamics of Emu Aggregations
Outside of the breeding season, emus are generally considered solitary creatures. Any larger collection, or “mob,” is typically a temporary aggregation driven by environmental necessity rather than complex social bonding. These loose gatherings form when resources become scarce, such as during periods of drought. When water sources become limited, many individual emus are compelled to congregate around the same reliable water hole or feeding area. Such mobs are transient and lack the coordinated social behaviors seen in truly gregarious bird species. They are simply sharing a common space for survival, and once the environmental pressure subsides, the mob disperses, and the emus return to their largely independent existence.
The Family Unit: Father and Chicks
The family unit centered on the male and his offspring is the most consistent and highly structured grouping in an emu’s life. After a female emu lays a clutch of eggs, it is the male who takes over the entire responsibility for incubation and rearing the young.
The male emu will sit on the nest for approximately 56 days without eating, drinking, or defecating, relying entirely on his stored body fat. After the chicks hatch, they remain under the father’s constant, protective care for an extended period. This small group, consisting of the father and his striped young, forms a cohesive and stable unit.
The father’s care can last for up to 18 months, during which time he fiercely guards the chicks against predators. He teaches them to forage and guides them through the harsh landscape until they are nearly fully grown. This enduring, reproductive-based grouping is the longest-lasting social bond in the emu’s life cycle, sharply contrasting with the ephemeral nature of the larger, resource-driven “mob.”