SCIENTIFIC NAME: Setophaga nigrescens
The Black-throated Gray Warbler is a small warbler having the same plumage color year-round.
Both sexes measures about 4.3 - 5.1 inches, with a wingspan of 7.5 - 7.8 inches and weight of 7 - 10 grams.
Adult males have gray upperparts, streaked with black on back. Wings have 2 white wing bars. Underparts are white, streaked with black on flanks. Undertail coverts are largely white.
Head, chin and throat are black, with white broad eyebrow and white broad moustache. There is a small yellow spot on the lores. Black bill is thin and pointed. Eyes are dark brown. Legs and feet are black.
Adult females are similar but paler and duller than males. They have a white chin spotted with black. Black throat is slightly mixed with white.
Both adults have same plumage all year-round, slightly washed with brownish in early autumn.
Immature birds resemble the females.
Immature females are duller with almost entirely white throat. Bill is browner than in adults.
CALL: Include typical “chip” note, sharp “chit” and “thick” or “tup” of medium amplitude. Flight note is a high “sip” or “see”.
SONG: Varied songs include buzzy “weezy-weezy-weezy-weet” insect-like, rising towards the end.
Feeds mainly on insects during breeding season, and small green caterpillars which are pests for oaks.
Breeds in coniferous or mixed woodlands with brushy undergrowth. Migrations and winter range are similar, with variety of forests, woodlands, scrubs and thickets.
Breeds in Western US, from southern British Columbia, Idaho and Wyoming, southwards to northern Mexico.
Winters in western Mexico. Birds follow mountain range and Pacific coastline southwards.
Nest is a deep open cup made with plant fibers, grass and weeds stalks. Interior is lined with feathers and hair.
It is situated on a horizontal branch about 2,50 - 10 meters above the ground, in different trees’ species such as Firs, Oaks, Pinyon Pines or Junipers. These birds are solitary nesters.
The female lays 3 - 5 creamy white eggs, with reddish-brown varied markings. She incubates them alone for about 12 days.
SOURCES:
http://www.oiseaux-birds.com
https://www.allaboutbirds.org
https://en.wikipedia.org