ARDENNA PACIFICA - (GMELIN, 1789)
Aves (Class) > Procellariiformes (Order) > Procellariidae (Family) > Ardenna (Genus)
Puffin fouquet, Puffin du Pacifique, Wedge-tailed shearwater, wigstaartpijlstormvogel, Keilschwanz-Sturmtaucher,
Description
Phase foncée et phase claire. Silhouette assez légère, longue queue cunéiforme. Phase sombre: plumage entièrement brun chocolat foncé, bec gris pattes couleur chair. Phase claire: un peu plus clair dessus, dessous du corps blanc, dessous des ailes blanc bordé de sombre, sous-caudales foncées et parfois bec couleur chair pâle. La phase sombre peut être confondue avec le Puffin à pieds pâles dans les zones où tous deux sont présents, mais elle se distingue par la queue, le bec, le vol plus rapide et plus gracieux. Taille : 46 cm. Envergure : 97 à 105 cm. Poids : 390 à 570 g. Longévité : 29 ans.
Vol
En général, vole à faible hauteur et bascule de gauche à droite en remontant, par temps calme quand il rase l'eau et vire, touche la mer avec l'aile inférieure et laisse un sillage. Quand le vent est plus fort, vire plus brusquement.
Chant
Les colonies de fouquets sont très bruyantes au début de la nuit, lorsque les oiseaux s'apprêtent à gagner les lieux de pêche au large. Une clameur extraordinaire faite de plaintes, de gémissements "inhumains", de cris, de lamentations s'élève de l'obscurité.
Habitat
Largement répandu dans les océans Indien et Pacifique. Plus d'un tiers de la population totale de ces oiseaux (soit environ 300 000) se trouve en Nouvelle-Calédonie, où ils sont appelés pétrels.
Alimentation
alimentation oiseaux de mer
Reproduction
Niche ça et là sur les îles et les côtes de l'Indien et du Pacifique, notamment en Australie (Est et Ouest). Le Fouquet creuse le sol meuble et sec, dans lequel il excave un tunnel à deux issues. Au centre, se trouve le nid proprement dit, qui ne comprend aucun aménagement. L'oeuf unique, très gros, à coquille blanche, est pondu à même le sol, puis couvé 47 à 53 jours. Il peut rester sans surveillance lorsque l'adulte part en recherche de nourriture. Les jeunes reviennent nicher sur les îles où ils sont nés.
Synonyms
Procellaria pacifica (Gmelin, 1789)
Puffinus pacificus (Gmelin, 1789)
Puffinus chlororhynchus (Lesson, 1831)
Procellaria carbonaria (G.R. Gray, 1844)
Puffinus sphenurus (Gould, 1844)
Puffinus pacificus royanus (Mathews, 1912)
Ardenna pacifica (Christidis & Boles, 2008)
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Description
The wedge-tailed shearwater is the largest of the tropical shearwaters. There are two colour morphs of the species, dark and pale; the pale morphs predominate in the North Pacific, the dark morph elsewhere. However, both morphs exist in all populations, and bear no relation to sex or breeding condition. The pale morph has grey-brown plumage on the back, head and upperwing, and whiter plumage below. The darker morph has the same dark grey-brown plumage over the whole body. The species’ common name is derived from the large wedge-shaped tail, which may help the species glide. The bill is dark and legs are salmon pink, with the legs set far back on the body (in common with the other shearwaters) as an adaptation for swimming.
Distribution and population
The Wedge-tailed Shearwater ranges across from throughout the tropical Pacific and Indian Ocean roughly between latitudes 35°N and 35°S, breeding on a large number of oceanic islands and on the east and west coasts of Australia. Reported from New Caledonia. The population is suspected to be in decline owing to unsustainable levels of exploitation, persecution, predation by invasive species and the over-exploitation of tuna fisheries.
Diet
Wedge-tailed shearwaters feed pelagically on fish, squid and crustaceans. Their diet is 66% fish, of which the most commonly taken is goatfish. It was thought that the species mostly took food from surface feeding, observations of feeding wedge-tails suggested that contact-dipping, where birds flying close to the surface snatch prey from the water was the most commonly used hunting technique. However, a 2001 study which deployed maximum depth recorders found that 83% of wedge-tails dived during foraging trips with a mean maximum depth of 14 m and that they could achieve a depth of 66 m (Burger, 2001).
Breeding behaviour
The wedge-tailed shearwater breeds in colonies on small tropical islands. Breeding seasons vary depending on location, with synchronised breeding seasons more common at higher latitudes. Northern hemisphere birds begin breeding around February, southern hemisphere birds begin around September. Wedge-tailed shearwaters display natal philopatry, returning to their natal colony to begin breeding at the age of four.
Wedge-tailed shearwaters are monogamous, forming a long term pair bond that lasts for several years. Divorce between pairs occurs after breeding seasons that end in failure. Nesting either in burrows or sometimes on the surface under cover. Pairs call frequently as a pair, both to reinforce the pair bond and warn intruders away from their territory. Parents also call to their chicks. The call is long, with an inhaling component (OOO) and exhaling component (err); their Hawaiian name ’ua’u kani means moaning petrel. Both sexes participate in digging a burrow, or repairing the burrow from last year. Nesting burrows of other species are also used. The breeding season of the Bonin petrel in Hawaii is timed to avoid that of the wedge-tail; in years where Bonin petrel chicks are still in burrows when wedge-tails return to begin breeding these chicks are killed or evicted. It attends these colonies nocturnally, although non-breeding wedge-tails are often seen at the surface throughout the day and breeding birds will rest outside their burrows before laying.
Both sexes undertake a prelaying exodus in order to build up energy reserves, this usually lasts around 28 days. A single egg is laid, if that egg is lost then the pair will not attempt another that season. After laying, the male usually undertakes the first incubation stint. Both sexes incubate the egg, in stints that can last up to 13 days. Incubation takes around 50 days. After hatching, the chick is brooded for up to six days, until it is able to thermoregulate, after which it is left alone in the nest while both parents hunt for food. It is initially fed with stomach oil, an energy rich waxy oil of digested prey created in the parent’s gut; later it is fed both solids and stomach oil. Like many procellariids, wedge-tailed shearwater parents alternate long and short trips to provide food, with the parents alternating between short foraging trips (1–4 days) and long trips (about 8 days), the two parents coordinating their feeding effort. Chicks increase in size to 560 g (larger than the adults) then drop to around 430 g before fledging. Fledging occurs after 103–115 days, after which the chick is independent of the adult.
Puffin fouquet, Puffin du Pacifique, Wedge-tailed shearwater, wigstaartpijlstormvogel, Keilschwanz-Sturmtaucher,
Description
Phase foncée et phase claire. Silhouette assez légère, longue queue cunéiforme. Phase sombre: plumage entièrement brun chocolat foncé, bec gris pattes couleur chair. Phase claire: un peu plus clair dessus, dessous du corps blanc, dessous des ailes blanc bordé de sombre, sous-caudales foncées et parfois bec couleur chair pâle. La phase sombre peut être confondue avec le Puffin à pieds pâles dans les zones où tous deux sont présents, mais elle se distingue par la queue, le bec, le vol plus rapide et plus gracieux. Taille : 46 cm. Envergure : 97 à 105 cm. Poids : 390 à 570 g. Longévité : 29 ans.
Vol
En général, vole à faible hauteur et bascule de gauche à droite en remontant, par temps calme quand il rase l'eau et vire, touche la mer avec l'aile inférieure et laisse un sillage. Quand le vent est plus fort, vire plus brusquement.
Chant
Les colonies de fouquets sont très bruyantes au début de la nuit, lorsque les oiseaux s'apprêtent à gagner les lieux de pêche au large. Une clameur extraordinaire faite de plaintes, de gémissements "inhumains", de cris, de lamentations s'élève de l'obscurité.
Habitat
Largement répandu dans les océans Indien et Pacifique. Plus d'un tiers de la population totale de ces oiseaux (soit environ 300 000) se trouve en Nouvelle-Calédonie, où ils sont appelés pétrels.
Alimentation
alimentation oiseaux de mer
Reproduction
Niche ça et là sur les îles et les côtes de l'Indien et du Pacifique, notamment en Australie (Est et Ouest). Le Fouquet creuse le sol meuble et sec, dans lequel il excave un tunnel à deux issues. Au centre, se trouve le nid proprement dit, qui ne comprend aucun aménagement. L'oeuf unique, très gros, à coquille blanche, est pondu à même le sol, puis couvé 47 à 53 jours. Il peut rester sans surveillance lorsque l'adulte part en recherche de nourriture. Les jeunes reviennent nicher sur les îles où ils sont nés.
Synonyms
Procellaria pacifica (Gmelin, 1789)
Puffinus pacificus (Gmelin, 1789)
Puffinus chlororhynchus (Lesson, 1831)
Procellaria carbonaria (G.R. Gray, 1844)
Puffinus sphenurus (Gould, 1844)
Puffinus pacificus royanus (Mathews, 1912)
Ardenna pacifica (Christidis & Boles, 2008)
----------------------------------------------
Description
The wedge-tailed shearwater is the largest of the tropical shearwaters. There are two colour morphs of the species, dark and pale; the pale morphs predominate in the North Pacific, the dark morph elsewhere. However, both morphs exist in all populations, and bear no relation to sex or breeding condition. The pale morph has grey-brown plumage on the back, head and upperwing, and whiter plumage below. The darker morph has the same dark grey-brown plumage over the whole body. The species’ common name is derived from the large wedge-shaped tail, which may help the species glide. The bill is dark and legs are salmon pink, with the legs set far back on the body (in common with the other shearwaters) as an adaptation for swimming.
Distribution and population
The Wedge-tailed Shearwater ranges across from throughout the tropical Pacific and Indian Ocean roughly between latitudes 35°N and 35°S, breeding on a large number of oceanic islands and on the east and west coasts of Australia. Reported from New Caledonia. The population is suspected to be in decline owing to unsustainable levels of exploitation, persecution, predation by invasive species and the over-exploitation of tuna fisheries.
Diet
Wedge-tailed shearwaters feed pelagically on fish, squid and crustaceans. Their diet is 66% fish, of which the most commonly taken is goatfish. It was thought that the species mostly took food from surface feeding, observations of feeding wedge-tails suggested that contact-dipping, where birds flying close to the surface snatch prey from the water was the most commonly used hunting technique. However, a 2001 study which deployed maximum depth recorders found that 83% of wedge-tails dived during foraging trips with a mean maximum depth of 14 m and that they could achieve a depth of 66 m (Burger, 2001).
Breeding behaviour
The wedge-tailed shearwater breeds in colonies on small tropical islands. Breeding seasons vary depending on location, with synchronised breeding seasons more common at higher latitudes. Northern hemisphere birds begin breeding around February, southern hemisphere birds begin around September. Wedge-tailed shearwaters display natal philopatry, returning to their natal colony to begin breeding at the age of four.
Wedge-tailed shearwaters are monogamous, forming a long term pair bond that lasts for several years. Divorce between pairs occurs after breeding seasons that end in failure. Nesting either in burrows or sometimes on the surface under cover. Pairs call frequently as a pair, both to reinforce the pair bond and warn intruders away from their territory. Parents also call to their chicks. The call is long, with an inhaling component (OOO) and exhaling component (err); their Hawaiian name ’ua’u kani means moaning petrel. Both sexes participate in digging a burrow, or repairing the burrow from last year. Nesting burrows of other species are also used. The breeding season of the Bonin petrel in Hawaii is timed to avoid that of the wedge-tail; in years where Bonin petrel chicks are still in burrows when wedge-tails return to begin breeding these chicks are killed or evicted. It attends these colonies nocturnally, although non-breeding wedge-tails are often seen at the surface throughout the day and breeding birds will rest outside their burrows before laying.
Both sexes undertake a prelaying exodus in order to build up energy reserves, this usually lasts around 28 days. A single egg is laid, if that egg is lost then the pair will not attempt another that season. After laying, the male usually undertakes the first incubation stint. Both sexes incubate the egg, in stints that can last up to 13 days. Incubation takes around 50 days. After hatching, the chick is brooded for up to six days, until it is able to thermoregulate, after which it is left alone in the nest while both parents hunt for food. It is initially fed with stomach oil, an energy rich waxy oil of digested prey created in the parent’s gut; later it is fed both solids and stomach oil. Like many procellariids, wedge-tailed shearwater parents alternate long and short trips to provide food, with the parents alternating between short foraging trips (1–4 days) and long trips (about 8 days), the two parents coordinating their feeding effort. Chicks increase in size to 560 g (larger than the adults) then drop to around 430 g before fledging. Fledging occurs after 103–115 days, after which the chick is independent of the adult.