Violet-green Swallow

Swallows and Martins are especially adapted to aerial life and in western North America the Violet-green swallow can been seen on the wing in urban and rural areas. This species breeds primarily in western North America from central Alaska and western Canada south to the Mexican highlands, rarely occurring east of the Rocky Mountains. It is a year round resident of the Mexican Baja and central Mexico. It winters mostly from Mexico south to Guatemala, El Salvador, and Honduras.

Adult Male (spring/summer)

Forehead and crown emerald green. White above eye extends around through auricular down chin, breast, belly, flanks, and sides of rump and undertail coverts. Above, soft velvety green or greenish bronze, with a very faint shade of purplish-violet concentrated on the nape into a transverse band. Often shows violet on the upper tail coverts. A white patch on each side of rump often brought close together so as to form an apparently continuous white band. Wingtips project beyond tail tip.

Adult Female (spring/summer)

Overall duller above than male.

Juvenile

Sooty gray on back and underparts washed with gray. Face is dusky.

General:

Small and very short-tailed swallow; wingtips project well beyond tail tip. Note white sides of rump. Length: 12cm. Wing: 27cm. Weight: 14grams.

Behaviour:

This and other swallows, as well as martins, spend more time in daylight flight feeding and soaring than most other North American passerines. It feeds in small groups or loose flocks. Like most other swallows, they feed exclusively on insects caught in flight, often at high altitudes. They nest both solitarily and in colonies of up to 25 pairs. The birds are often highly gregarious during foraging, migration, and when away from their nests, and flocks of several hundred birds are commonly observed in these contexts.

Habitat:

Occurs principally in montane coniferous forests, often nesting in inaccessible sites such as cliffs, crevices, abandoned woodpecker holes in tall dead snags. It is also common in western suburban areas nesting in cavities in homes and buildings.

Information:

Despite an extensive distribution, less is known about the Violet-green Swallow than nearly any other North American swallow. This swallow appears to be the western counterpart of is congener, the Tree Swallow. 
Of note, the male sings courtship songs in flight in the dark before sunrise, repeating over and over “tsip tseet tsip”. Females typically lay 4-6 white eggs in an abandoned woodpecker hole, crevice in a cliff, building, or bird box, often returning to the same breeding site in successive years.

Similar species:

Tree Swallow.

Conservation Status:

Listed as Least Concern. Populations appear to be stable.

Capture Rates:

Migrating from Central America, the Violet-green Swallow prefers mountainous coniferous forests for breeding. The low capture rate (2010-2012; standardized as birds captured per 100 net hours) from April through June reflect the small number of Violet-green Swallows breeding at Colony Farm.

Molt Summary:

PF: HY complete (Aug-Oct); PB: AHY complete (Aug-Sep); PA absent (?)

Sexing:

Males like this AHY bird in June have entirely iridescent green and purplish upperparts including the crown. The cheek and postocular area are bright white contrasting with the dark green crown.

Females like this AHY bird in April have bright green and purplish upperparts with some brownish/olive mixed in the crown. The cheek and postocular area are mottled grayish not contrasting markedly with the crown.

Females also have grayish feathers in the rump whereas males have entirely iridescent purple rumps.