Chestnut-collared Swallow

The chestnut-collared swallow is 12 to 12.5 cm (4.7 to 4.9 in) long and weighs 14 to 18 g (0.49 to 0.63 oz). Both sexes of both subspecies have essentially the same plumage. Adults have a dark chestnut forecrown and hindneck. Their crown and back are glossy blue-black with white streaks on the mantle and their rump is chestnut. Their ear coverts and throat are white that sometimes has a buff tinge. Their wings and tail are blackish brown. Their underparts are partially white with a rufous-chestnut band across the upper breast, rufous-chestnut flanks, and a brown or chestnut vent. They have a black bill, pinkish brown legs, and black feet. Juveniles are duller and browner than adults.

Subspecies P. r. aequatorialis of the chestnut-collared swallow is the more northerly of the two. It is found in southwestern Ecuador from central Manabí Province south about to the Peruvian border in Loja Province. The nominate subspecies is found from there south in Peru through Lima Department. The species primarily inhabits agricultural areas and their associated towns. In elevation it ranges from sea level to about 2,000 m (6,600 ft) in Ecuador and to 1,000 m (3,300 ft) in Peru.

The chestnut-collared swallow's diet has not been studied. It is assumed to feed on insects captured in mid-air like other swallows. It forages in flocks that often include other swallow species, usually low to the ground over fields and around buildings.