Gaviotín Peruano/Peruvian Tern/Sternula lorata

Nombre en español: Gaviotín Peruano

Nombre en inglés: Peruvian Tern

Nombre científico: Sternula lorata

Categorías: Amenazado / En Peligro (EN) / Hipotéticas

Canto: Alvaro Jaramillo

El charrancito peruano, gaviotín peruano, gaviotín chico, gaviotín churri-churri o chirriche (Sternula lorata) es una especie de ave caradriforme de la familia que suele vivir en el Pacífico sur.

El charrancito peruano mide unos 24 centímetros de largo. Forma parte de la avifauna que gira en torno a la corriente de Humboldt, por lo que se distribuye por la zona desértica de la costa del Pacífico, desde Ecuador por el norte hasta Tarapacá y Antofagasta (Chile) por el sur. Es común de la costa del Perú. Su alimentación consiste en peces pequeños y algunos crustáceos.

Descripción

Mitad superior de la cabeza y nuca, de color negro, la frente es blanca. La garganta, el mentón y la zona auricular baja son blancas también. El dorso, lomo, cobertoras, supracaudales y cola son de color gris apizarrado. El pecho, flancos y abdomen son de un gris pálido. La región subcaudal es blanca. Tienen la barba externa negra y la interna de grisácea a blanca. El pico es amarillento con culmen y punta negros. Sus patas son amarillentas y sus ojos pardos.

Peruvian tern

The Peruvian tern (Sternula lorata) is a species of tern in the family Laridae. Found in northern Chile, Ecuador, and Peru, its natural habitats are hot deserts, sandy shores, and coastal saline lagoons. It is threatened by habitat loss.

In Spanish, it is known as the «charrancito Peruano»^[1] or «gaviotín chico».

Description

The Peruvian tern is a very small species with a length of about 24 cm (9.4 in). The upper half of the head and neck are black, and the remaining part of the head is white. The back, wings and tail are grey, the throat, chin and breast are white, and the chest, belly and flanks are pale grey. The under tail-coverts are white. The bill is yellow with a black tip, the irises are brown and the legs are yellowish. The pale grey underparts differentiate it from other small terns. It has a very rapid and characteristic wingbeat. The call is a shrill «kik» and a harsh «gree», and it also utters a descending series of «kee-ee-eer» notes.

Distribution

This species is endemic to the tropical west coast of South America. Its range extends from north and central Ecuador, through Peru to northern Chile, as far south as the Mejillones Peninsula. Its status in Ecuador is unclear and in Peru it is known from four confirmed sites, breeding at the back of the beach in association with wetlands. There are nine known sites in Chile, all in the vicinity of Mejillones, and at all of these the birds breed a little inland in the desert. There may be other breeding sites that have yet to be discovered, and some sites have not been revisited since they were recorded many years ago.

Ecology

The diet has been observed to include the Peruvian anchoveta (Engraulis ringens), the Atlantic saury (Scomberesox saurus), the Peruvian silverside (Odontesthes regia) and the mote sculpin (Normanichthys crockeri).

Breeding takes place between August and February but is mostly concentrated between October and January. The nests are widely separated in loose colonies of up to twenty-five pairs. They are often found near coastal wetlands and lagoons where the birds forage. Some birds nest on beaches and dunes one to two hundred metres inland from the high tide mark, but others nest one or more kilometres inland on sandy plains One or two eggs form a clutch, and both eggs and chicks are well-camouflaged to avoid detection. After breeding, the birds leave the coast and may move out to sea. In El Niño years, they are also absent from the shore, do not make any attempt to breed and probably remain at sea.

Status

The total number of Peruvian terns is estimated to be in the range 1,000 to 2,499 individuals. The number seems to be declining, and in 2007 it was suggested that there were only half as many birds as there had been ten years earlier. Because of the small population size and the decrease in numbers of individuals, BirdLife International has assessed the bird’s conservation status as being «endangered». The Chilean Ornithologist Jürgen Rottmann is the director of The Gaviotín Chico Sustainability Foundation which has successfully rallied the local community school students, councilmen and the mining industry, to protect the nesting habitad of this bird at the Mejillones Peninsula from stray dogs and other predators that exacerbate human-caused decline. The strategies used include labeling and fencing of the nesting sites, translocation of predators and the use of decoy Japanese quail eggs.