page_title: Purple martin
section_title: Breeding
hierarchical_section_title: Purple martin / Behavior / Breeding
caption_attribution_description: Progne subis English: Purple Martins eggs and small chicks in a nestbox in Tulsa, Oklahoma, USA. May 18, 2010 nest check in colony&#160;: 32 eggs; 2 young; 7 nests.
context_page_description: The purple martin is the largest swallow in North America. Despite their name, purple martins are not truly purple. Their dark blackish-blue feathers have an iridescent sheen caused by the refraction of incident light giving them a bright blue to navy blue or deep purple appearance. In some light they may even appear green in color.
  Their breeding range extends from central Alberta down through the eastern United States. Subspecies breed in Baja California, Arizona, and New Mexico. Purple martins are migratory passerines. Most make a brief stopover in the Yucatán Peninsula or Cuba during pre-breeding migration to North America and during post-breeding migration before reaching their overwintering site in South America.
  They are known for their speed, agility, and their characteristic mix of rapid flapping and gliding flight pattern. When approaching their nesting site, they will dive from the sky at great speeds with their wings tucked.
context_section_description: Males arrive in breeding sites before females, and establish their territory. A territory can consist of several potential nest sites. After forming a pair, both the male and female inspect available nest sites. This process is complicated by the fact that artificial nest sites could be houses with many rooms, clustered gourds, or single gourds. The nest is made inside the cavity of such artificial structures and retains a somewhat flat appearance. The nest is a structure of primarily three levels: the first level acts as a foundation and is usually made up of twigs, mud, small pebbles and in at least a few reported cases, small river mollusk shells were used; the second level of the nest is made up of grasses, finer smaller twigs; the third level of construction composing the nest, is a small compression usually lined with fresh green leaves where the eggs are laid.
  Purple martins are generally known to raise only a single brood. The average clutch size is four to six eggs per nest. Females lay one egg a day and incubation begins when the penultimate (second to last) egg is laid. Incubation lasts 15–16 days and the female is the main incubator, with some help from the male. Hatching occurs over the course of two to three days. Fledging, when the young leave the nest, occurs between 26–32 days after hatch day. Fledglings will continue to receive care from both parents for up to a month after fledging.
caption: Eggs and small chicks in a nest box in Oklahoma, United States
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