About Forpus xanthopterygius (Spix, 1824)
Forpus xanthopterygius, commonly known as the cobalt-rumped parrotlet or blue-winged parrotlet, is a parrot species belonging to the family Psittacidae. This species has two recognized subspecies: Salvadori's cobalt-rumped parrotlet (F. x. flavescens) and Hellmayr's cobalt-rumped parrotlet (F. x. flavissimus).
Cobalt-rumped parrotlets are distributed across most of central and northern South America, with each subspecies occupying a separate portion of the species’ total range. The species is generally common and widespread, though it occurs only in more localized areas within the Amazon Basin. They primarily live in lowland habitats, including dry woodlands, riparian woodlands, cerrado, caatinga, palm groves, semi-arid scrubland, savanna, and pastures. They tend to avoid dense forested areas and do not live at altitudes above 1,200 metres (3,900 ft). Most populations of cobalt-rumped parrotlets are non-migratory. However, populations in Argentina make local movements aligned with the flowering seasons of the plant species they eat, and populations in the Brazilian Atlantic Forest are altitudinal migrants.
The typical breeding season for cobalt-rumped parrotlets runs from May to August, but occupied nests have been observed in July, January, and March in different parts of the species’ range. Females lay 3 to 7 small, white, roughly spherical eggs. Some cobalt-rumped parrotlets have been observed scraping clay nests built by rufous horneros with their beaks. The reason for this behavior is not fully clear. Cobalt-rumped parrotlets do use abandoned rufous hornero nests to raise their own young, leading to the suggestion that the birds are “taste-testing” the nest material to check if it meets their unknown suitability standards. Similar studies of other Forpus species have concluded that clay-licking supplies these birds with important minerals that they cannot get through other food sources.
