Black-crowned Tchagra

Identificazione

The black-crowned tchagra is a colourful and unmistakable species, 19–22 cm in length. It has a black crown and eye stripes separated by a broad white supercilium. The underparts are pale grey and the upperparts pale brown. The folded wings are chestnut and the tail is black, tipped white. The bill is black.<p>Sexes are similar, but young birds have a brown cap and a pale yellow bill. There are 14 subspecies, varying in size and the colour of the back, underparts and eyestripe.<p>Black-crowned tchagra has a descending whistling song, chee-chee chee cheroo cheroo, and can be readily tempted into sight by imitating this call, presumably because the bird is concerned that there is an intruder in its territory. The male also has a switchback display flight.

Tassonomia

In 1760 the French zoologist Mathurin Jacques Brisson included a description of the black-crowned tchagra in his Ornithologie based on a specimen collected in Senegal. He used the French name La pie-griesche gris du Sénégal and the Latin Lanius Senegalensis cinereus. Although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature. When in 1766 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition, he added 240 species that had been previously described by Brisson. One of these was the black-crowned tchagra. Linnaeus included a brief description, coined the binomial name Lanius senegalus and cited Brisson's work. The species is now placed in the genus Tchagra that was introduced by the French naturalist René Lesson in 1831. Nine subspecies are recognised.

Nome scientifico

Tchagra senegalus

Autorità

(Linnaeus, 1766)

Ordine

Passeriformi

Famiglia

Malaconotidi

Genere

Tchagra

Areale e habitat

Migrazione

Specie stanziale

Comportamento

Comportamento migratorio: Specie stanziale.

Conservazione

Tendenza della popolazione: stabile.

Tendenza della popolazione

stabile