Ақкөкейлік ұсаққұйрық құс

Species of bird

The pale breasted spinetail (Synallaxis albescens) is a passerine bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Costa Rica, Panama, Trinidad, and in every mainland South American country except Chile and Ecuador.

The pale breasted spinetail's taxonomy is in flux. The International Ornithological Committee (IOC) recognizes these 11 subspecies: The IOC includes hypoleuca within latitabunda and griseonota within inaequalis. What is now the dark breasted spinetail (S. albigularis) was previously treated by some authors as conspecific with the pale breasted spinetail. Some now treat them as sister species. This article follows the IOC 11 subspecies model.

The pale breasted spinetail is believed to be a year round resident in most of its range, though the farthest southern sub population might make some northern movement after the breeding season.

The pale breasted spinetail feeds on a wide variety of arthropods, and also includes small snails in its diet. It usually forages in pairs, gleaning prey from grass, foliage, small branches, and at times the ground. It usually stays below about of the ground.

The pale breasted spinetail's breeding season varies geographically but is generally within the local spring and summer. Though it is a member of the ovenbird family, which is named for the clay nests many species make, the pale breasted spinetail constructs a globe of grass and thorny sticks with a horizontal entrance tube. The tube and inner chamber are lined woth soft plant material. The nest is typically placed in bunch grass or in a vine covered bush, usually within of the ground and rarely as high as The clutch size is two to four eggs. The incubation period is 15 to 18 days and fledging occurs about 16 days after hatch. The species is thought to be monogamous, and both members of the pair incubate the clutch and care for nestlings.

The pale breasted spinetail sings for long periods. Its song is variously described as "a sharp, scratchy zwee bit, zweebit", a "very high scratchy wéetjirr wéetjirr", an "incessantly repeated wee tee", an "unceasing, very high, shrill 'zutsweet zutsweet ' ", a repeated "wee bidget wee bidget ", and "a buzzy, nasal 'wéé byew', 'wáke up', 'wa tér' ". A call in Costa Rica is a "sharp 'bip' " that is often repeated and followed by a "long rattling 'churrr' ". In Brazil its call is described as an "extr. high 'tsweét' ".

The IUCN has assessed the pale breasted spinetail as being of Least Concern. It has an exremely large range and its estimated population of 50 million mature individuals is believed to be stable. No immediate threats have been identified. It is considered fairly common to common in most of its range though local in southeastern Brazil. It is "[t]olerant of moderate anthropogenic disturbance, provided that adequate areas of tall grass remain [and is expanding] its range in areas that have been cleared".