Austral storm petrels, belonging to the family Oceanitidae and the smallest of seabirds, are found in all the world's oceans. These birds feed primarily on planktonic crustaceans and small fish, often hovering to pick food from the water's surface with their distinctive fluttering flight. They breed almost exclusively at sea, only coming ashore to nest colonially, usually in burrows or crevices, and visit their breeding sites at night to avoid predators. They showcase high site fidelity, often returning to their birthplace to breed, and exhibit long-term monogamy with shared parenting duties such as incubation, which can last up to 50 days, and chick rearing for an additional 70 days. These petrels have various adaptations for flight, including hovering and surface pattering, where they pick at water's surface for food, and dynamic soaring. The ten species within this family are distributed across five genera, with some, like the New Zealand storm petrel thought to have been extinct until 2003, are now facing threats due to human activities and invasive species on their breeding islands. Their taxonomy and evolutionary history indicate they are basal within their order, and some suggest they should be split into distinct families. Morphologically, they are the tiniest seabirds with elongated skulls and elongated legs, which they can hardly use to support themselves for long ambulations on land. Despite their small size, they can live for up to 30 years. Conservation efforts are critical for some of these species, which are considered threatened or endangered due to introduced predators like rats and feral cats which they are ill-equipped to deal with.