They are dumpy, short-necked, pigeon-like birds with white plumage, black bills, caruncles and facial skin.

Coastlines and intertidal zones of subantarctic islands, especially around seabird and seal colonies, as well as the vicinity of human habitation.

Sheathbills are opportunistic omnivores, predators and scavengers, feeding on strandline debris, algae and other vegetation, as well as on invertebrates, fish, seabird eggs and chicks, seal milk, blood, placentas, carrion, faeces, rodents and human refuse.

Nests in crevices, caves and under boulders on untidy piles of vegetation and debris from seabird and seal colonies.

At risk from scavenging toxic wastes and from introduced predators such as feral cats, but large, scattered range with no evidence of significant overall population decline leads to conservation status assessment of Least Concern.