Gavion Cocinero/Kelp Gull/Larus dominicanus

Foto: Cesar Chillon

Nombre en español: Gavion Cocinero

Nombre en ingles: Kelp Gull

Nombre científico: Larus dominicanus

Familia: Laridae

Categorías: Errática

Canto: Peter Boesman

La gaviota dominicana o gaviota cocinera (Larus dominicanus) es una especie de ave Charadriiforme de la familiaLaridae que habita las costas e islas del Hemisferio Sur.

Descripción

Los adultos tienen las partes superiores y alas de color negro. La cabeza, pecho, vientre y cola son de color blanco. El pico es amarillo con una mancha roja y las patas tienen coloración amarilla. Miden entre 55 y 60 cm de largo y unos 128 cm de largo alar. La llamada o canto es estridente. Los juveniles tienen el dorso negro-castaño escamoso y tardan cuatro años en alcanzar la madurez.2​ Se han observado alimentándose de las ballenas francas vivas por lo menos desde 1996.

Hábitat

Es una gaviota principalmente costera. El nido es una depresión poco profunda en la tierra con vegetación y plumas. La hembra normalmente pone 2 o 3 huevos. Ambos padres alimentan los polluelos jóvenes. Se encuentra en variadas zonas, desde costas hasta incluso la Patagonia y Antártida. Sus poblaciones se están expandiendo debido a la oferta alimenticia de los basurales a cielo abierto, ocupando ecosistemas de agua dulce5.

Alimentación

Son pájaros omnívoros como la mayoría de las gaviotas del género Larus; recogen basura y presas pequeñas para alimentarse.

Subespecies

Existen cuatro subespecies de Larus dominicanus:4

  • Larus dominicanus vetula – se distribuye en África del Sur
  • Larus dominicanus dominicanus – es la subespecie encontrada alrededor de América del Sur y partes de Australia, donde solapa con la gaviota del Pacífico.
  • Larus dominicanus judithae
  • Larus dominicanus melisandae
  • Larus dominicanus austrinus – se distribuye sólo en la Antártida.5

Kelp gull

The kelp gull (Larus dominicanus), also known as the Dominican gull, is a gull which breeds on coasts and islands through much of the southern hemisphere. The nominate L. d. dominicanus is the subspecies found around South America, parts of Australia (where it overlaps with the Pacific gull), and New Zealand (where it is known as the southern black-backed gull, simply the black-backed gull, or by its Māori name karoro). L. d. vetula (known as the Cape gull) is a subspecies occurring around southern Africa.

The specific name comes from the Dominican Order of friars, who wear black and white habits.[

Description

The kelp gull superficially resembles two gulls from further north in the Atlantic Ocean, the lesser black-backed gull and the great black-backed gull and is intermediate in size between these two species. This species ranges from 54 to 65 cm (21 to 26 in) in total length, from 128 to 142 cm (50 to 56 in) in wingspan and from 540 to 1,390 g (1.19 to 3.06 lb) in weight. Adult males and females weigh on average 1,000 g (2.2 lb) and 900 g (2.0 lb) respectively. Among standard measurements, the wing chord is 37.3 to 44.8 cm (14.7 to 17.6 in), the bill is 4.4 to 5.9 cm (1.7 to 2.3 in) and the tarsus is 5.3 to 7.5 cm (2.1 to 3.0 in).[3][4][5] The adult kelp gull has black upperparts and wings. The head, underparts, tail, and the small «mirrors» at the wing tips are white. The bill is yellow with a red spot, and the legs are greenish-yellow (brighter and yellower when breeding, duller and greener when not breeding). The call is a strident ki-och. Juveniles have dull legs, a black bill, a dark band in the tail, and an overall grey-brown plumage densely edged whitish, but they rapidly get a pale base to the bill and largely white head and underparts. They take three or four years to reach maturity.

Subspecies

There are five subspecies of kelp gull. The African subspecies L. d. vetula is sometimes split as the Cape gullL. vetula. It has a more angular head and a smaller shorter bill. The adult has a dark eye, whereas the nominate kelp gull usually has a pale eye. Young Cape gulls have almost identical plumage to similarly aged kelp gulls.

  • L. d. dominicanus, (Lichtenstein, 1823): South America, Falklands, South Georgia, Australia & New Zealand
  • L. d. vetula, (Bruch, 1853): southern Africa
  • L. d. judithae, (Jiguet, 2002): subantarctic islands in the Indian Ocean
  • L. d. melisandae, (Jiguet, 2002): southern & southwestern Madagascar
  • L. d. austrinus, (Fleming, 1924): Antarctica & Antarctic islands

Behaviour

Kelp gulls are omnivores like most Larus gulls, and they will scavenge as well as seek suitable small prey. They gather on landfills and a sharp increase in population is therefore considered as an indicator for a degraded environment. Kelp gulls have been observed feeding on live right whales since at least 1996. The kelp gull uses its powerful beak to peck down centimetres into the skin and blubber, often leaving the whales with large open sores, some of which have been observed to be half a meter in diameter. This predatory behavior has been documented in Argentinian waters, and continues today. At rocky sites along the southern African coast, such as at Boulders Beach in Cape Town, kelp gulls (Larus dominicanus vetula) can be seen picking up shellfish and repeatedly flying up several meters and dropping them onto the rocks below in order to break them open. They have also been reported pecking the eyes out of seal pups on the coast of Namibia before attacking the blind seals in a group.[

The nest is a shallow depression on the ground lined with vegetation and feathers. The female usually lays 2 or 3 eggs. Both parents feed the young birds.

Wikipedia/eBird/xeno-canto

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