Belding yellow throats

from Wikipedia, the free encyclopedia
Belding yellow throats
The subspecies Geothlypis beldingi goldmani

The subspecies Geothlypis beldingi goldmani

Systematics
Order : Passerines (Passeriformes)
Subordination : Songbirds (passeri)
Superfamily : Passeroidea
Family : Wood Warbler (Parulidae)
Genre : Yellow throat ( Geothlypis )
Type : Belding yellow throats
Scientific name
Geothlypis beldingi
Ridgway , 1883

The Belding's yellow throat ( Geothlypis beldingi ) is a small songbird from the genus of the yellow throats ( Geothlypis ) in the wood warbler family (Parulidae). Robert Ridgway named it after the American ornithologist Lyman Belding . The distribution area is located in Baja California Sur on the narrow peninsula Baja California in Mexico . The IUCN has listed the species as "critically endangered" since 2000.

features

Belding yellow throats reach a body length of 14 centimeters and weigh 13.8 to 17.7 grams. The wing length is 6 to 6.4 centimeters in the male and 5.7 to 6 centimeters in the female. They are similar in appearance to the Bahamian yellow throat ( Geothlypis rostrata ). Adult male Belding yellow throats of the nominate form have a black face mask that is connected to one another above the beak, an adjoining wide, yellow forehead band that extends below the ear covers and an olive-green to brown-tinged crown and neck plumage. The wings and tail feathers are dull brown with olive feather edges. The upper side plumage is olive green with faded olive flanks and sides of the chest, the lower side plumage is light yellow, somewhat more dull on the belly. The beak is black; the legs are flesh-colored.

The adult female Belding yellow throats lack the black face mask and the forehead band. The crown plumage is olive green with brown pigments. The reins and ear covers are gray-olive and the narrow superciliar stripe and the interrupted eye ring are olive-yellow. The upper side plumage is olive green; the underside plumage pale yellow, often with whitish abdominal plumage. The plumage is faded olive-brown on the flanks. Male individuals of the subspecies Geothlypis b. goldmani have a gray-white forehead crown band.

Occurrence, nutrition and reproduction

Belding's yellow throats have a very fragmented range. They are endemic to the state of Baja California Sur, Mexico . Belding's yellow throats inhabit freshwater swamps with vegetation consisting of reeds , bulrushes or common rushes and the edges of lagoons . They mainly feed on insects and other invertebrates that they find in the lower vegetation. It incubates from March to May. From a height of 1.5 meters, they build their deep, bowl-shaped nest in cattails or sometimes on the common pond rush. The nest is built from parts of the inhabited water plants and blades of grass, and the inside of the nest is padded with animal hair and fine plant fibers. A clutch consists of two to four eggs (usually three). There are no studies on the incubation and nestling time.

Subspecies

The systematic division into two subspecies is not generally accepted. Some zoologists consider the Belding yellow throat to be monotypical with different color variations.

There are two recognized subspecies:

Together with the willow yellow throat ( Geothlypis trichas ), the Bahamian yellow throat ( Geothlypis rostrata ) and the gold-crowned yellow throat ( Geothlypis flavovelata ) the Belding yellow throat forms a super species . Some authors, the willow and Belding's yellowthroat is also considered conspecific considered.

Hazard status and inventory figures

They have been listed by the IUCN as "critically endangered" since 2000. The main cause is habitat destruction. According to the bird protection organization BirdLife International, there are occurrences of the nominal form of around 70 birds in Punta San Pedros and 219 to 480 in San José del Cabo. In the past, the subspecies also occurred in the south of the state of Baja California to north of La Paz in Baja California Sur. However, the population collapsed due to habitat destruction. The subspecies Geothlypis b. goldmani occurs with around 537 to 648 individuals around the city of San Ignacio and around 203 to 405 individual animals around Mulegé and La Purísima. There are other deposits in Comondú ; however, the population size is unknown. Formerly they were also widespread around Santiago, Miraflores and El Triunfo, but there they were exterminated.

swell

literature

  • Jon Curson, David Quinn, David Beadle: New World Warblers. Helm, London 1994, ISBN 0-7136-3932-6 .

Web links

Commons : Belding's Yellow throat  - Collection of images, videos and audio files