Africa Wild Bird Book

[Dewi]

035. Great Shearwater Puffinus gravis (Grootplymstormvoël)
Order: Procellariiformes. Family: Procellariidae



Description
This shearwater is 43–51 cm in length with a 105–122 cm wingspan. Gray-brown upper parts with dark cap, U-shaped white band at base of tail. White rump. White of underside extends up sides of neck, sometimes across nape. Thin dark grey bill. The legs and feet are pink.
Similar species: Similar in size to Cory's Shearwater but distinguished by its distinctive dark cap, dark, not yellow, bill, overall darker upperparts, barred brown-and-buff back, dark patch on the lower belly and less marked white underwing. Cory's Shearwater has a heavier yellow bill, dark head, clean white underwing, and blunt broad wings.
Manx Shearwater is much smaller with no white collar, no white tail band, totally white belly and undertail coverts, and much more blackish.

Distribution
Atlantic Ocean. Breeds at Tristan da Cunha, Gough Island and to a lesser extent the Falkland Islands, after which it disperses across the Atlantic and South-west Indian Oceans, including in southern African waters. Here it is most common off the Western, Northern and Eastern Cape and southern Namibia, while more scarce off northern Namibia and KwaZulu-Natal.

Habitat
Pelagic.

Movements and migrations
Trans-equatorial migrant, as virtually its entire population stays in southern African waters from April-May before migrating to the North-west Atlantic Ocean from late May to early August, at which point it heads south to the South Atlantic Ocean (including southern African waters). It stays from about August-November before returning to its breeding colonies.

Diet
Mainly eats fish and plankton, doing most of its foraging by grabbing prey from the water surface or plunge-diving. It often follows dolphins, toothed whales and other aquatic predators, catching prey that they drive to the water surface.

Breeding
This shearwater nests in large colonies. Lays one white egg in a small burrow or in the open grass, which it visits only at night to avoid predation by large gulls.

Status
Rare vagrant in summer to offshore waters.

[Dewi]

035. Great Shearwater Puffinus gravis (Grootplymstormvoël)

© Michele Nel

Links:
Sabap2
ARKive: http://www.arkive.org/great-shearwater/puffinus-gravis/
Sasol
Trevor Hardaker Photos

[Dewi]

037. Sooty Shearwater Puffinus griseus (Malbaartjie)
Order: Procellariiformes. Family: Procellariidae



Description
Upperparts uniform dark brown. Underparts uniform dark brown with silvery flashes to the underwing and silvery lining, conspicuous in flight.The white on the underwings of is most prominent on the median primary coverts. The flight feathers usually appear all dark. Its bill is dark. On the water, Sooty Shearwaters appear evenly dark. The folded wingtips extend to, or just past, the tail.

Distribution
All oceans from Arctic to Antarctic circle. Absent in Northern Indian Ocean, central Pacific and central South Atlantic. Breeds on islands off southern South America, south-eastern Australia, Tasmania and New Zealand as well as on the Falklands and Tristan da Cunha. In the non-breeding season it disperses across the Pacific, Atlantic and Southern Oceans down to about 65° South, including southern African waters. Here it is abundant off the western and southern coasts from central Namibia to the Western and Eastern Cape and KZN, in fact it is the most common winter seabird in this area. It is less common further out to sea, while completely absent east of Mozambique.

Habitat
Pelagic.

Movements and migrations
The breeding season is from September-April, after which it migrates to the North Atlantic and North Pacific Oceans. Juveniles and non-breeding adults are present year-round in southern African waters, although the latter are thought to subsequently migrate north.

Diet
Small fish, cephalopoda and crustaceans. It mainly eats small fish, supplemented with crustaceans, crab larvae, tunicates and trawler discards, doing most of it foraging by grabbing prey from the water surface and plunge-diving up to a depth of about 67 m. In order to do this it dives in a zig-zag pattern, which reduces bouyancy by expelling air trapped in its feathers. It also associates with Cape fur seals, tunas, Common dolphins, Dusky dolphins and Bryde's whales, catching prey that they drive to they drive to the surface.

Breeding
They breed in small islands in the south Pacific and south Atlantic Oceans, mainly around New Zealand, the Falkland Islands and Tierra del Fuego. October onwards. They breed in huge colonies and the female lays 1 white egg. They nest in burrows lined with plant material which are visited only at night to avoid predation by large gulls. Single egg incubated for 53-56 days. Chicks fledge after 86-106 days.

Status
Common offshore visitor to the region.

[Dewi]

037. Sooty Shearwater Puffinus griseus (Malbaartjie)



Links:
Species text in The Atlas of Southern African Birds
Sabap2: http://sabap2.adu.org.za/spp_summary.ph ... &section=3
ARKive: http://www.arkive.org/sooty-shearwater/ ... s-griseus/
Sasol
Trevor Hardaker Photos

[Dewi]

038. Manx Shearwater Puffinus puffinus (Swartbekpylstormvoël)
Order: Procellariiformes. Family: Procellariidae



Description
34 cm. All dark above with white underparts. Underwing has dark leading and trailing edge. White wing linings, white crescent behind eye, short tail. Undertail dark with white vent.
Similar species: Cory's Shearwater is much larger with much lighter brown body and wings, heavy yellow bill and white tail band. Great Shearwater is much larger with lighter body, smudgy brown belly, neat cap, narrow pointed wings and white tail band.

Distribution
Breeds at islands at temperate North Atlantic Ocean off western Europe and North America, after which it heads south to the South Atlantic Ocean, mainly off eastern South-America but also in annually increasing numbers in southern African waters. Here it is fairly common off the coast of Namibia and the Northern and Western Cape, especially near the Cape Peninsula, while more scarce further out to sea and off the Eastern Cape.

Habitat
Pelagic.

Movements and migrations
Departs from its breeding colonies in August and September and migrates through the tropics to the east coast of South America and southern African waters. It stays here from October-February before returning to its breeding colonies by February-April.

Diet
It mainly eats pelagic schooling fish such as Anchovies (Engraulis encrasicolus) supplemented with cetacean faeces and offal from fishing vessels, doing most of its foraging by grabbing from the water surface or diving to greater depths.

Breeding
Nests colonially in burrows on grassy slopes of islands, often at some distance from the sea. Visits burrows after dark.

Status
Uncommon visitor to offshore waters.

[Dewi]

038. Manx Shearwater Puffinus puffinus (Swartbekpylstormvoël)



Links:
Sasol,
Oiseaux net - Puffin des Anglais,
Trevor Hardaker Photos

[Toko]

ORDER PROCELLARIIFORMES Family Hydrobatidae (Storm-petrels)

Storm-petrels were formally considered to be a part of the Procellariidae, but are now generally accepted as a separate family, they are visually separated by having only a single opening serving both their nostrils. They are difficult birds to identify because they are all very similar in size and colour. Most species being black with a white rump. There are two main groups of Storm Petrels, one of Northern Hemisphere birds which have long pointed wings and in most species a slightly forked tail, and a Southern Hemisphere group which have shorter more rounded wings and longer legs, some Southern species are also have paler coloured bellies. Some Southern species also exhibit polymorphism in their colouration, meaning not all members of the species have the same colouration.
Storm Petrels are all small birds, the largest being only 25 cm long. They have an average wingspan of 45 cm. They are difficult birds for most people to see because they spend all their lives at sea when not breeding, and even during the breeding season they only come to land after dark and leave again before dawn. This is probably an adaptation to avoid aerial predators. They feed on Zooplankton, mostly crustaceans and other small marine organisms which they pick from the surface whilst flying over the sea. These include squid, as well as insects in the form of Halobates spp. (Heteroptera: Gerridae). At times they appear to be almost walking on the water as they tend to have their feet extended downwards to the waters surface while feeding. Many species like the European Storm-Petrel (Hydrobates pelagicus) are great ship followers.
Several species undertake some of the longest migrations know such as Wilson's Storm-Petrel Oceanites oceanicus which travels in a figure eight each year from its Antarctic breeding grounds to the subartic non-breeding season feeding grounds and back again. Other species have only small migrations or do not migrate at all. In one species at least, White-faced Storm-Petrel Pelagodroma marina, some populations migrate across the equator while others do have lesser migrations and some merely appear to disperse after breeding rather than migrating.
As with other small petrels most species nest in holes, often quite deep ones, though a few species will nest in rock crevices. The nest itself is rudimentary, or non-existent. Also like all the Procellariiformes they lay only one white egg per breeding season. The nests are almost exclusively made on uninhabited offshore islands
On land they are quite ungainly and many species have difficulty standing on their feet. Instead they tend to rest both their feet and tarsi on the ground to stand on and to walk with. They are adept in the air however and some species such as Wilson's Storm-Petrel Oceanites oceanicus are recorded as indulging in intricate aerial chases as a part of their courtship behaviour They are highly vocal birds, especially during the breeding season and around the colony. Their calls being described as a twittering, whirring, churring and creaking. Calls include flight calls, distress calls and a variety of antagonistic calls used in nest burrow defence. There appears to be a wide range of variability between and within species as the the way calls are used, which has made it difficult for human observers to quantify them, but the birds seem to understand each other OK.
Digging a nest burrow, especially if the soil is stony can be energetically expensive work for a small bird and existing burrows are therefore important possessions. Birds digging burrows have severely warn bills and claws. (This applies to all the hole or burrow nesting petrels). Fights involving attempted usurpation of a nest owner, even one incubating an egg are not an unusual and can become quite physical, normally the possessor remain in possession.

[Toko]

Species indigenous to southern Africa:

Family Hydrobatidae (Storm-petrels)
Oceanites oceanicus Wilson's Storm-petrel 044
Garrodia nereis Grey-backed Storm-petrel
Pelagodroma marina White-faced Storm-petrel
Fregetta grallaria White-bellied Storm-petrel 045
Fregetta tropica Black-bellied Storm-petrel 046
Hydrobates pelagicus European Storm-petrel 042
Oceanodroma leucorhoa Leach's Storm-petrel 043
Oceanodroma matsudairae Matsudaira's Storm-petrel 918

[Dewi]

044. Wilson's Storm-petrel Oceanites oceanicus (Geelpootstormswael)
Order: Procellariiformes. Family: Hydrobatidae



Description
Length: 15-19 cm. Wingspan: 38-42 cm. A small dark Storm Petrel with brown crescents on the upperwing, and the dark underwing has a paler patch on the underwing-coverts. U or V shaped white rump which wraps around the sides to the vent. Wings are short and rounded. Legs black with bright yellow webs. Identified in flight by the bold white rump extending onto sides of uppertail-coverts, and legs protruding beyond square-ended tail.
Similar species: From above, Black-bellied Storm Petrel and White-bellied Storm Petrel show a brown back and the compact, square-tailed appearance of Oceanitidae, but are larger with longer and broader wings. Their pale ulnar band is less distinct and narrower than on Wilson's. Larger than European Storm Petrel, it has broader, more rounded and flattened wings, and long, spindly legs that usually project beyond the end of the tail.It seldom occurs in dense flocks like the European Storm-Petrel.

Distribution
Oceanic. Worldwide from the Tropic of Canced Sout, but reaches further North in the Atlantic, sometimes to the South of Greenland. Breeds in ice-free areas of Antarctica (O. o. exasperatus), the sub-Antarctic islands (O. o. oceanicus) and islands around the Cape Horn of South America. It disperses in the non-breeding season across all seven of the oceans of the world, including much of southern African waters, travelling closer to the coastline than most other storm-petrels. It is most commonly seen along the border between the continental shelf and the deep ocean shelf.
Wilson’s Storm Petrel is a common non-breeding visitor, occurring throughout the region, but most frequent off the west and south coasts where it can be extremely abundant. It is scarce off KwaZulu-Natal and Mozambique. Both subspecies occur off southern Africa, with Antarctic birds being more frequent.

Habitat
Pelagic. It is found in all waters, but is most numerous over the continental shelf.

Movements and migrations
Most leave the breeding colonies in the period from March-May, which is also when its numbers peak in southern African waters. Here it is present year-round, however many birds return to their colonies around October-December.

Diet
Crustaceans, especially krill, fish and small squid.
Its diet in southern Africa is not as well known as in its breeding colonies, where it mainly eats planktonic crustaceans supplemented with fish, squid and carrion. It mainly forages by taking prey from the water surface (submerging its head and neck), often "walking" on the water beforehand while in flight (see photo on the top right). The following food items have been recorded in its diet in southern Africa: zooplankton, small squid, Lampanyctodes hectoris (Lanterfish), fishery waste.

Breeding
Lays November-December. It makes nests in burrows or rock crevices, and tends to breed together in loose colonies. The breeding season is around November to December. Each pair lays a single egg, which hatches after an incubation period of 38-59 days. Chicks fledge after 60 days.

Status
Common visitor to offshore waters in the region, especially during winter months.

[Dewi]

044. Wilson's Storm-petrel Oceanites oceanicus (Geelpootstormswael)





Links:
Species text in The Atlas of Southern African Birds: http://sabap2.adu.org.za/docs/sabap1/044.pdf
Sabap2: http://sabap2.adu.org.za/spp_summary.ph ... &section=3
Sasol
Identification of ‘black-and-white’ storm-petrels
ARKive: http://www.arkive.org/wilsons-storm-pet ... oceanicus/
More photos by Dewi: https://africawild-forum.com/viewtopic.p ... t=60#p3624