The Passerina Rositae, also known as the rose-bellied bunting or Rosita’s bunting, belongs to the family Cardinalidae, which is commonly known as cardinals or cardinal grosbeaks. This bird species can be found in a small area in southern Mexico and is unique to that region.
The rose-bellied bunting is a small bird that measures 13.5 to 14.5 cm (5.3 to 5.7 in) and weighs around 19.5 to 20.5 g (0.69 to 0.72 oz). The male has a purplish-blue crown and electric blue upperparts that gradually fades from dark to light towards the tail. Its chin is grayish, the throat and chest are blue, while the belly and vent area are salmon pink. On the other hand, the adult female has gray-brown head and upperparts with a bluish tinge on the rump. Its undersides are pinkish buff, with the throat being warmer and becoming paler towards the lower belly.
The rose-bellied bunting is typically found in a limited area along the Pacific slope of the Isthmus of Tehuantepec in eastern Oaxaca and western Chiapas. There has only been one additional sighting of this species in El Triunfo Biosphere Reserve in Chiapas. These birds can be found in various types of forest environments such as arid to semiarid thorn forests, moister gallery forests, and swamp forests. Their habitat elevation ranges from 180 to 800 meters (590 to 2,620 feet).
When it comes to finding food, the rose-bellied bunting prefers to forage solo or with a partner in the lower to middle region of its home. Its menu includes grass seeds and fruit from trees and shrubs.
Observations have been made on two nests of rose-bellied buntings. The first nest, discovered in late July, contained newly laid eggs while the second nest found in late June had partially incubated eggs. These open cup nests were constructed using dead leaves and bark, lined with softer material, and placed in the junctures of small tree trunks. One nest had three eggs and the other contained four eggs. No further details on the breeding patterns of these birds have been recorded.
The rose-bellied bunting has a delightful singing style, which can be described as a pleasant, slightly muffled warble. Additionally, its call sounds like a moist “plik” or “plek”.
The rose-bellied bunting has been evaluated by the IUCN and classified as Near Threatened. One of the reasons for this classification is its limited range, which may be dwindling due to degradation of its natural habitat and development of infrastructure.