Arrendajo Euroasiático

Identificación

The Eurasian jay is a relatively small corvid, similar in size to a western jackdaw (Coloeus monedula) with a length of 34–35 cm (13–14 in) and a wingspan of 52–58 cm (20–23 in). The nominate race has light rufous brown to a pinkish brown body plumage. The whitish throat is bordered on each side by a prominent black moustache stripe. The forehead and crown are whitish with black stripes. The rump is white. The complex colouring on the upper surface of the wing includes black and white bars and a prominent bright blue patch with fine black bars. The tail is mainly black.<p>The most characteristic call is a harsh, rasping screech that is used upon sighting various predators and as an advertising call. The jay is well known for its mimicry, often sounding so like a different species that it is difficult to distinguish its true identity unless the bird is seen. It will imitate the calls of birds of prey such as the mew of the common buzzard and the cackle of the northern goshawk.

Taxonomía

The Eurasian jay was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Corvus glandarius. Linnaeus specified the locality as "Europa" but this was restricted to Sweden by Ernst Hartert in 1903. The Eurasian jay is now one of three species placed in the genus Garrulus that was established in 1760 by the French zoologist Mathurin Jacques Brisson. The genus name Garrulus is a Latin word meaning "chattering", "babbling" or "noisy". The specific epithet glandarius is Latin meaning "of acorns".<p>Eight racial groups (33 subspecies in total) were recognised by Steve Madge &amp; Hilary Burn in 1994: <p>The International Union for Conservation of Nature (IUCN) and Birdlife International split the Eurasian jay into three species. The subspecies G. g. leucotis becomes the white-face jay (Garrulus leucotis) and the bispecularis group containing six subspecies becomes the plain-crowned jay (Garrulus bispecularis).

Nombre científico

Garrulus glandarius

Autoridad

(Linnaeus, 1758)

Orden

Passeriformes

Familia

Córvidos

Género

Garrulus

Distribución y hábitat

A member of the widespread jay group, it inhabits mixed woodland, particularly with oaks, and is a habitual acorn hoarder. In recent years, the bird has begun to migrate into urban areas, possibly as a result of continued erosion of its woodland habitat. Before humans began planting the trees commercially on a wide scale, Eurasian jays were the main source of movement and propagation for the European oak (Q. robur), each bird having the ability to spread more than a thousand acorns each year. Eurasian jays will also bury the acorns of other oak species, and have been cited by the National Trust as a major propagator of the largest population of holm oak (Q. ilex) in Northern Europe, situated in Ventnor on the Isle of Wight. Jays have been recorded carrying single acorns as far as 20 km, and are credited with the rapid northward spread of oaks following the last ice age.

Migración

Especie residente

Comportamiento

Patrón migratorio: Especie residente.

Conservación

Tendencia poblacional: estable.

Tendencia poblacional

estable