Spectacled Petrel (Procellaria conspicillata)

Spectacled Petrel

[order] PROCELLARIIFORMES | [family] Procellariidae | [latin] Procellaria conspicillata | [authority] Gould, 1844 | [UK] Spectacled Petrel | [FR] Haplospize unicolore | [DE] Weisskinn Sturmvogel | [ES] Pardela Gorgiblanca | [NL] Brilstormvogel

Subspecies

Genus Species subspecies Region Range
Procellaria conspicillata SO widespread

Genus

The Procellaria petrels represent a group of large and bulky seabirds that can be placed between the shearwaters of the genus Calonectris and the more fulmarine petrels. Until recently the largest of the Procellaria-species, the White-chinned and the only slightly smaller Spectacled Petrel, were considered to be conspecific. Now they are split into two separate species. Both have a large and strong bills, ivory colored with black sulci between the horny plates and ivory colored ungues, the latter sometimes slightly darker in the Spectacled Petrel. The Westland and Parkinson?s Petrel are also two similar species, of which the latter is a smaller version of the first. Both have ivory colored bills (with a bluish tinge in young birds), with blackish ungues. In the Parkinson’s the black is less extensive than in the Westland. There is no overlap in bill measurements. The Westland Petrel is of the same size as the White-chinned and its culmen is always longer than 47.8 mm. That of the Parkinson?s Petrel not longer than 45.1 mm The bill of the somewhat distinct Grey Petrel is about the size of the larger Procellarias, with the same pattern as the White-chinned and pectacled, but instead of ivory, more pearl-grey. The Grey Petrel’s somewhat lighter bill structure comes close to that of the Calonectris species. Because its somewhat different coloration, habits and structure this species formerly formed a genus of its own: Adamastor. It is now considered to belong to Procellaria.

Physical charateristics

Large, black petrel with white bands around face. Sooty-black with white face markings. Horn or yellow bill. Similar spp. Provided face markings seen, easily distinguished from other petrels.


wingspan min.: 134 cm wingspan max.: 147 cm
size min.: 51 cm size max.: 58 cm
incubation min.: 57 days incubation max.: 62 days
fledging min.: 87 days fledging max.: 106 days
broods: 1   eggs min.: 1  
      eggs max.: 1  

Range

Southern Ocean : widespread. Procellaria conspicillata is essentially confined to the South Atlantic Ocean north of the South Pacific Oceanlar Front, predominantly between 25-41 degrees S19. It breeds only on the high western plateau of Inaccessible Island, Tristan da Cunha, St Helena (to UK)

Habitat

It breeds in wet heath above 380 m. Burrows are along the banks of river valleys and in adjacent marshy areas.

Reproduction

Little is known about its reproductive biology, but egg-laying generally commences around mid-October, with a single egg being incubated in a nest burrow. The incubation and fledgling periods are unknown, but are presumed to be similar to those of the white-chinned petrel at 57 to 62 days and 87 to 106 days respectively. The main natural predator of the spectacled petrel, and especially of fledglings, is the southern skua (Catharacta Antarctica).

Feeding habits

The spectacled petrel feeds on squid, crustaceans and small fish, but is also known to regularly scavenge for offal thrown from ships, and to attempt to seize bait from the hooks of long lines

Conservation

This species is listed as Vulnerable because, despite apparent population increases, significant numbers are caught as bycatch in longline fisheries, and, owing to its very small breeding range, it is highly susceptible to stochastic events and human activities.
Feral pigs may have caused the apparent extirpation of Procellaria petrels from Amsterdam Island and may have had an impact on Inaccessible throughout most of the 19th and early 20th centuries. Southern Skua Catharacta antarctica is a natural predator, particularly of fledglings, and there is a permanent risk of colonisation by mammalian predators, particularly black rat Rattus rattus from Tristan. The greatest threat comes from interactions with longline fisheries, given estimates of more than 200 killed annually off southern Brazil during the late 1980s and early 1990s
Spectacled Petrel status Vulnerable

Migration

Outside the breeding season, it is mostly restricted to the Atlantic region, with most birds dispersing to the coastal waters off southern Brazil, while small numbers may also be seen off the west coast of southern Africa.

Distribution map

Spectacled Petrel distribution range map

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