page_title: American cliff swallow
section_title: Description
hierarchical_section_title: American cliff swallow / Description
caption_attribution_description: Cliff swallow; Neal Herbert; August 2014; Catalog #19687d; Original #3638
context_page_description: The American cliff swallow is a member of the passerine bird family Hirundinidae, the swallows and martins. The scientific name is derived from Ancient Greek; Petrochelidon originates from the petros meaning "rock" and khelidon "swallow", pyrrhonota comes from purrhos meaning "flame-coloured" and -notos "-backed".
  American cliff swallows are extremely social songbirds that can be found in large nesting colonies reaching over 2,000 nests. They are frequently seen flying overhead in large flocks during migration, gracefully foraging over fields for flying insects or perching tightly together on a wire preening under the sun.
  Cliff swallows build gourd-shaped nests made from mud with small entrance holes. They build their nests tightly together, on top of one another, under bridges or alongside mountain cliffs. Living in large populations, these aerial insectivores use extensive vocalizations to communicate warnings or food availability to the other individuals.
context_section_description: The American cliff swallow's average body length is 13 cm (5.1 in), they have short legs and small bills with relatively long pointed wings. Adult cliff swallows have an overall dark brownish plumage covering both their back and wings, they have a characteristic white forehead, rich red coloured cheeks with a dark throat, basic white underparts and a buffy-coloured rump. In good lighting occasions, their crowns and mantle feathers are iridescent. The Northern population is slightly larger in body size from the Mexican cliff swallow population and differ in facial markings, where the Mexican population have a chocolate brown patch on their forehead.
  The male and females have identical plumage, therefore sexing them must be done through palpation of the cloaca. During breeding season, the males will have a harder cloaca that is more pronounced because the seminal vesicles are swollen. In addition, during incubation females will lose feathers on their lower breast to create a warm patch for sitting on their eggs. American cliff swallows are similar in body plumage colouring to the related barn swallow species but lack the characteristic fork-shaped tail of the barn swallow prominent during flight. The cliff swallows have a square-shaped tail.
  Juvenile American cliff swallows have an overall similar body plumage colouring to the adults, with paler tones. The juveniles lack the iridescent adult plumages, and their foreheads and throats appear speckled white. The juvenile cliff swallows’ white forehead and throat markings have high variance between unrelated individuals than those from the same clutch. These distinctive white facial markings disappear during maturity following their complex-basic moult pattern, because their pre-formative plumage is different than the basic plumage. The pre-formative facial plumage has been suggested as a possible way for parents nesting in large colonies to recognize their chicks.
caption: Juvenile American cliff swallow in gourd-shaped mud nest
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