Description wikipedia

The purple martin (Progne subis) is a passerine bird in the swallow family Hirundinidae. It is the largest swallow in North America. Despite its name, the purple martin is not truly purple. The dark blackish-blue feathers have an iridescent sheen caused by the diffraction 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. Being migratory, their breeding range extends from central Alberta down through the eastern United States. Subspecies breed in Baja California, Arizona, and New Mexico. 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 patterns. When approaching their nesting site, they will dive from the sky at great speeds with their wings tucked, just like the peregrine falcon does when hunting smaller birds.