Africa Wild Bird Book

[Dewi]

Antarctic Prion Pachyptila desolata (Antarktiese Walvisvoël)
Order: Procellariiformes. Family: Procellariidae



Description
25-28 cm. A small, blue-grey prion with a well-defined, dark 'M' across the upperwing. Fairly broad black tip to the grey wedge-shaped tail. Underparts and underwings white. Dusky grey patches on sides of the breast. Blue-grey bill is moderately wide when viewed from above. White supercilium and dark line through the eye. Blue feet. Like all prions, flight fluttery and erratic.
Similar species: The Antarctic Prion is most similar in bill structure to Salvin’s Prion, and two also have very similar facial markings. The main characters used to distinguish them in the hand are that the Antarctic prion generally has a brighter blue bill with a larger nail at the tip, straighter sides to the bill when viewed from above, and lamellae (comb-like filters) not visible from the side when the bill is closed. In contrast, Salvin’s Prion has a slightly larger grey-blue bill with relatively weaker nail, bowed sides to the bill when viewed from above, and lamellae visible when the bill is closed. Bill measurements of the two overlap (Salvin’s Prion 13.5-17.5 mm wide; Antarctic Prion 11-15.5 mm wide). Slender-billed Prion has paler facial markings and a narrower bill (9.3-12.5 mm).

Distribution
Breeds on Antarctica and sub-Antarctic islands, migrating north to temperate southern oceans when gets too cold. It is seasonally abundant in across most of southern Africa's waters, while more scarce off the east and north-western coasts.

Habitat
Oceanic.

Movements and migrations
Breeds from October-April, after which it heads north to warmer waters, staying in southern Africa from about May-August.

Diet
Crustaceans, celaphopods, gastropods & small fish.

Breeding
Antarctic Prion arrive at their colonies in October to early November. They nest on exposed rock faces of cliffs, in cavities under boulders or in short twisting burrows in soft grass-covered slopes. Experienced breeders are the first to appear, and often return to the same site they used the previous year. The females will leave the nesting site for approximately 14 days before laying, but the males will reappear at night keeping the nest hole free from snow. One egg is laid in December, and hatches in late January to mid-February. The egg is incubated by both members of the pair for a total of 45 days. The male takes the first shift. Departure of the chicks and adults occurs in mid-March, 45-55 days after hatching. Adults and fledglings move into subantarctic and temperate waters for the winter months, regularly reaching Australia

Status
Common Winter visitor offshore.

[Dewi]

Antarctic Prion Pachyptila desolata (Antarktiese Walvisvoël)





Links:
Sabap2
Trevor Hardaker Photos

[Dewi]

Salvin's Prion Pachyptila salvini (Salvinse Walvisvoël)
Order: Procellariiformes. Family: Procellariidae



Description: Salvin's Prion is a small 29 cm petrel with grey and white plumage, and a blue bill.
Similar species: All prion species are very similar in appearance and behaviour, differing mainly in bill shape. All are medium-small seabirds that are blue-grey above and white below, with a blackish ‘M’ across the back from wingtip to wingtip, a black tip to the upper tail, blue-grey bill, and blue legs and feet.
Slightly smaller than Broad-billed Prion with slightly smaller head and blue bill slightly narrower than same. Black on tail narrowish and does not extend to the outer tail feathers which is more noticeable when tail is spread. The Broad-billed Prion has a more massive bill (18.7-24.3 mm wide) that is darker than that of other prions (lead-grey, shading to blue at the widest margins, and with a blue lower mandible).
Very much like the Antarctic Prion, but with a somewhat smaller collar and longer blue bill. The main characters used to distinguish them in the hand are that Salvin’s Prion generally has a slightly larger, darker bill (13.5-17.5 mm wide) with a smaller nail at the tip, outwardly-bowed sides to the bill when viewed from above, and lamellae (comb-like filters) that are visible from the side when the bill is closed. In contrast, the Antarctic Prion has a slightly smaller (11-15.5 mm wide), bluer bill with relatively larger nail, straight sides to the bill when viewed from above, and the lamellae are not visible when the bill is closed.

Distribution
Occurs throughout the southern Indian Ocean, usually staying below the Subtropical Front (38-40° South). It is a vagrant to southern African waters, with isolated records in the north-eastern corner of the region and along the coast of South Africa.

Habitat
Oceanic.

Diet
It mainly eats small crustaceans (especially amphipods), supplemented with small fish, squid and chaetognaths.

Breeding
Monogamous. This prion breeds colonially on a number of subantarctic islands in the southern Indian Ocean. The colonies are attended nocturnally in order to avoid predation by skuas. Nests are hidden in burrows dug into the soil. A single egg is laid in November or early December, which is incubated for around 50 days. Both parents share the incubation duties and feed the chick once it is hatched. Fledging occurs about 60 days after hatching.

Status
Probably a rare Winter visitor far offshore. Nearest breeding colonies on Marion Island.

[Dewi]

Salvin's Prion Pachyptila salvini (Salvinse Walvisvoël)





Links:
Sabap2

[Dewi]

029. Broad-billed Prion Pachyptila vittata (Breëbekwalvisvoël)
Order: Procellariiformes. Family: Procellariidae

Description
Largest Prion. 25-30 cm. Appears large headed with steep forehead and black bill which is broad at the base. Typical Prion with blue-grey upperparts and a dark "M" across the wings and back. Dark cap. Narrow black tip to tail. Underparts white.
Note that within all Prion species there is variation in bill size, tail markings, upperpart colouration and overall size between different populations of the same species. It has a bill that is both more massive (18.7-24.3 mm wide) and darker than all other prion species. The bill is lead-grey, shading to blue at the widest margins, and with a blue lower mandible. The Broad-billed Prion is also darker on the upper breast than other prions, with blue-grey tabs extending from the shoulders to almost form a collar.
Similar species: Salvin’s Prion is the ‘next-broadest’ of the prions (bill 13.5-17.5 mm wide). It is a slightly smaller bird, with a bluer bill.

Distribution
Breeds on Tristan da Cunha, Gough Island and islands off New Zealand, after which it disperses across the southern oceans. It is rare vagrant to southern Africa, with a few records of stranded birds on the coast of the Western Cape and central Mozambique, as well as at sea in the south-western corner of the region.

Habitat
Oceanic.

Diet
Crustaceans and small squid. It mainly eats small crustaceans by filtering them through its serrated bill, or alternatively grabbing large prey, such as fish and squid, from the water surface.

Breeding
Broad-billed Prions are colonial breeders, nesting as monogamous pairs. Breeding begins on the coastal slopes of the breeding islands in July or August. They nest in burrows on islands. They lay their single egg in a burrow type nest. Both parents incubate the egg for 50 days, and then spend another 50 days raising the chick.

Status
Probably a rare Winter visitor far offshore.

[Dewi]

029. Broad-billed Prion Pachyptila vittata (Breëbekwalvisvoël)



Links:
Sabap2

[Dewi]

027. Kerguelen Petrel Aphodroma brevirostris (Kerguelense Stormvoël)
Order: Procellariiformes. Family: Procellariidae

Description
A small, grey-brown petrel with silvery white wing flashes. It is sooty-grey all over, with black bill, and pink-and-black legs and feet. The underwing is uniformly dark, but can reflect low sunlight to appear silvery at the base of the main flight feathers. It appears large-headed and short-necked, with a steep forehead. The bill appears deep and robust in side profile, with a prominent nasal tubes and terminal hook. From above, the bill is surprisingly narrow.

Distribution
Southern Oceans. Breeds on sub-Antarctic islands in the period from August-February, after which it disperses across the southern oceans, generally staying within 40-70° South. It is usually not present in southern Africa, with only 17 records before 1984, although between July-August 1984 at least 233 individuals occurred from the area west of the Northern Cape to coastal KwaZulu-Natal (the last record of it in southern African waters), with eruptions at the same time off South America and Australasia.

Habitat
Pelagic.

Diet
It mainly eats crustaceans and squid, supplemented with fish and offal, doing most of its foraging at night by grabbing prey from the water surface.

Breeding
The species attends its colonies nocturnally, breeding in burrows in wet soil. The burrows usually face away from the prevailing wind. A single egg is laid per breeding season; the egg is unusually round for the family. The egg is incubated by both parents for 49 days. After hatching the chick fledges after 60 days

Call
Silent at sea.

Status
Vagrant to offshore regions.

[Dewi]

027. Kerguelen Petrel Aphodroma brevirostris (Kerguelense Stormvoël)



Links:
Sasol
Trevor Hardaker Photos

[Dewi]

026. Atlantic Petrel Pterodroma incerta (Bruinvlerkstormvoël)
Order: Procellariiformes. Family: Procellariidae

Description
One of the largest gadfly petrels (Pterodroma species), recognised by its striking white breast and abdomen that contrast with the uniformly black-brown plumage of the rest of the body. Particularly sharp colour demarcation exists from the brown upper breast to the white lower breast and belly. In worn plumage, the breast and throat can appear mottled brown but never pure white. Underwings dark with paler bases to the primaries. Sexes are alike.
Similar species: Much larger than Soft-plumaged Petrel and is brown, not grey.

Distribution
South Atlantic Ocean from Tropic of Capricorn South to the Southern tip of South America and South Africa. Breeds at Gough Island and Tristan da Cunha, after which it disperses across the South Atlantic Ocean, mainly between 20-60° South. It is a rare vagrant to southern Africa, with most records in the south-western corner of the region, with other sightings off central Namibia and southern South Africa; all were sighted between July-November.

Habitat
Pelagic.

Diet
Predominantly squid, but also fish and crustaceans, doing most of its foraging by catching prey from the water surface.

Breeding
Nesting occurs in burrows dug in peaty soils in fern-bush vegetation from 50 to 300 metres above sea level on Gough, and at higher elevations on Tristan. Atlantic petrels return to their colonies from February to March in order to mate. Single eggs are laid from June to July, with young hatching in August and September, and fledging in December and January.

Status
Rare winter vagrant to the region. Classified as Endangered (EN) on the IUCN Red List.

[Dewi]

026. Atlantic Petrel Pterodroma incerta (Bruinvlerkstormvoël)



Links:
NEWMAN'S VOELS VAN SA (8ste UIT)