All species › Tubenoses › Petrels, shearwaters and diving petrels › Black-winged Petrel
Black-winged Petrel | Pterodroma nigripennis
Zwartvleugelstormvogel | Petrel ala negra
The Black-winged Petrel is the commonest small gadfly petrel in this region and at the same time the easiest of a difficult group: a thirty-centimetre bird that looks white from below with a crisp black outline, and shows a broad black diagonal right across the underwing. Over islands such as Norfolk and Macauley it forms noisy, acrobatic flocks in summer.
Voice
At sea it is nearly always silent. Over the colony it is anything but: displaying groups chase one another through the air with an accelerating, ever shriller ki-ki-ki-ki-ki, alongside high whistles whis-whis-whis or wee-wee-wee. From the ground and the burrow come lower, hiccupping ha-ha-ha notes. On Norfolk Island this sound is one of the familiar noises of summer from October to March.
No freely licensed recording has been found for this species yet; what to listen for is described below.
Identification
A small gadfly petrel of thirty centimetres and about a hundred and sixty grams. The head is pale grey with a black-and-white speckled forehead and a clear dark eye patch; the upperparts are grey with a dark M across the wings and rump. An extensive grey collar runs onto the otherwise white underparts. The decisive feature is on the underwing: a broad dark band along the leading edge of the outer wing that continues as a broad black diagonal stripe well onto the inner wing, while the rest of the underwing stays white. Seen from below the bird therefore reads as white with a sharply drawn black outline. Bill black and hooked, twenty-three to twenty-six millimetres long; legs usually pink, sometimes blue or mauve. The tail is pointed.
Confusion species
Within the genus this is the species against which the other small ones are measured. Cook's Petrel (Pterodroma cookii) and Pycroft's Petrel (Pterodroma pycrofti) show only a thin dark line along the leading edge and lack the broad black diagonal across the inner underwing; they are also paler above and lack the heavy grey collar. Gould's Petrel (Pterodroma leucoptera) has a dark cap running below the eye and so looks hooded rather than pale-headed. Chatham Island Petrel (Pterodroma axillaris) is the closest match: it has the same diagonal bar, but in that species it runs on into black axillaries — that armpit patch is diagnostic and is worth checking on every bird. A species not itself covered by this guide but which can turn up here, Pterodroma brevipes, usually shows a dark collar or a dark belly and a quite different black-and-white pattern on the underwing.
Habitat
At sea, mainly subtropical water north of the subtropical convergence, over deep water beyond the shelf. It breeds on islets and along cliff edges and grassy slopes of larger islands, digging its burrow in soft ground under grass, ferns or low scrub, often on steep slopes just above the sea.
Where the bird is most often found, arranged by main group and formation.
Range and movements
The centre of gravity is the Kermadec Islands, where Macauley Island alone holds two to three million pairs and Curtis Island some three hundred thousand. It also breeds on the Three Kings, Motuopao, Matapia, Simmonds, Motukokako, Burgess, East Island and Portland Island, and in small numbers on Rangatira and Mangere in the Chatham group. In the western half of the window it breeds on Lord Howe and on Phillip Island beside Norfolk Island, with flocks from those colonies often circling over land. Outside the breeding season it migrates to the North Pacific, to an area north-west of Hawaii; in the Australian summer it is a regular sight on pelagics off New South Wales and southern Queensland.
- Breeding (summer)
- dark = core range, pale = thinly spread
Where and when to look
On Norfolk Island you do not even need to go to sea: look up at the cliff edges late in the afternoon between October and March and dozens of birds will be screaming after one another. To see it offshore, take a pelagic out of Sydney or Wollongong between December and April. When a small gadfly comes past, go straight to the inner underwing: a broad black diagonal makes the bird, and the black axillaries of Chatham Island Petrel are then the only thing left to rule out.
Conservation
Least Concern (LC), and with millions of birds on the Kermadecs alone this is one of the most abundant seabirds in New Zealand. Wherever introduced mammals reached the breeding islands it disappeared, and the species has gained greatly from the removal of rats and cats on the Kermadecs, on Norfolk Island and, in 2019, on Lord Howe: new islets have been recolonised since. What remains on land is mainly volcanic activity on the Kermadecs and fire; fisheries mortality appears slight in this small, high-flying species.
Scientific name
Pterodroma nigripennis | (Rothschild, 1893)
Rothschild described the species in 1893 as Oestrelata nigripennis, so author and year stand in parentheses. nigripennis is Latin for black-winged, from niger (black) and penna (feather or wing), and refers to the black wing markings that the English name carries too. The type locality is the Kermadec Islands, still the heart of its range. The genus Pterodroma was introduced by Bonaparte in 1856, from Greek pteron (wing) and dromos (runner).