Common Diving Petrel

Identification

The common diving petrel is a small, plump seabird measuring 200 to 250 mm in length and weighing around 86 to 186 grams. It features black plumage above and dull white below, with a relatively short black bill and distinctive thin white strips on the wings. The legs and feet are blue with blackish-brown webbing, while the face and neck may appear more brown than black. Unless observed at close range, it is nearly indistinguishable from the South Georgian diving petrel, though the common diving petrel has brown inner web primary feathers (compared to light feathering in its relative), smaller and narrower bills, and lacks the posterior black line down the tarsi found on the South Georgia species.

Range & Habitat

The common diving petrel is found between latitudes 35 and 55 degrees south, distributed across the South Atlantic islands, subantarctic islands of the Indian Ocean, New Zealand waters, and south-eastern Australian islands. Six subspecies occupy different regions, from the Tristan da Cunha archipelago to the Falkland Islands, Chatham Islands, and Australian coastlines. The species is native to islands and islets rather than mainland coasts, where it inhabits vegetated slopes where it digs burrows approximately 1.5 metres long, though burrows are occasionally constructed on flatland.

Behaviour & Diet

The common diving petrel is a specialist wing-propelled diver, capable of diving to depths of 60 metres while hunting for prey. Its diet is dominated by crustaceans, and it forages predominantly at night, targeting vertically migrating plankton. During the breeding season, it feeds on the continental shelf near shore, though its movements and feeding range during the non-breeding season—which lasts only two months annually—remain poorly understood. It occasionally ventures into deeper pelagic waters outside the breeding period.

Breeding occurs in large colonies with dense nest spacing of approximately one nest per square metre. Pairs form monogamous relationships, though mating habits are not extensively documented. Females lay a single white egg measuring 38 by 29 millimetres, incubated for 53 to 55 days. Chicks are brooded for 10 to 15 days and fledge at 45 to 59 days, with both parents sharing offspring care. Young are grey-downed when hatched, and the species has a life expectancy of 6.5 years.

Best Time & Places to See It

The common diving petrel's non-breeding movements remain poorly known, making timing recommendations uncertain. However, breeding colonies on subantarctic and southern ocean islands offer the best opportunities for observation. Key locations include islands off New Zealand such as the Chatham Islands, Snares, Stewart Island, and the Antipodes Islands; South Atlantic sites including South Georgia, the Falkland Islands, and Tristan da Cunha; and southern Indian Ocean islands such as Kerguelen, Heard, and McDonald Islands. Visiting during breeding season would increase encounter likelihood, though access to remote colonies is often restricted.

Photography Tips

Photographing the common diving petrel presents challenges due to its small size, remote island habitat, and nocturnal feeding behaviour. The bird's plumage contrast—black upperparts against white underparts—provides natural photographic appeal when well-lit. Given the species' similarity to the South Georgian diving petrel, careful attention to bill size and feather details will be necessary for identification in photographs. Night photography may capture feeding behaviour on migrating plankton, though this requires specialized equipment and patience. The blue legs and feet provide distinctive colour accents worth highlighting when possible.