Blue-grey gnatcatcher

Polioptila caerulea

(Photo from Internet Bird Collection)

Common name:
blue-grey gnatcatcher (en); balança-rabo-azulado (pt); gobemoucheron gris-bleu (fr); perlita grisilla (es); blaumückenfänger (de)

Taxonomy:
Order Passeriformes
Family Polioptilidae

Range:
This species breeds in the North America, as far north as southern Oregon and southern Wyoming in the west, but as far as Michigan, Maine and marginally into Canada in the east, and also throughout Mexico, in northern Guatemala, in the Bahamas and in the Turks and Caicos Islands. The more northern population migrate south to winter as far south as Cuba and the Honduras.

Size:
These birds are 10-12 cm long and have a wingspan of 16 cm. They weigh 5-7 g.

Habitat:
The blue-grey gnatcatcher is found in various scrubland and woodland habitats, particularly in temperate forests and dry tropical forests, but also moist tropical forests, mangroves, swamp forests, dry savannas, dry scrublands and second growths. They occur from sea level up to an altitude of 2.100 m.

Diet:
They feed on small arthropods, such as treehoppers, froghoppers, leaf hoppers, plant bugs, tree bugs, leaf beetles, weevils, wolf spiders, caterpillars and grasshoppers.

Breeding:
Blue-grey gnatcatchers breed in April-July. They are monogamous and both sexes cooperate in building the nest, an open cup made of plant stems, bark strips and grasses, held together by spider webs, and lined with plant down, paper, cocoons, hair, or feathers. It is attached to a branch using spider webs. The female lays 3-5 pale blue eggs with reddish-brown spots, which are incubated by both sexes for 11-15 days. the chicks are fed by both parents and fledge 10-15 days after hatching. Pairs often raise 2 broods per season.

Conservation:
IUCN status - LC (Least Concern)
This species has a very large breeding range and the global population is estimated at 160 million individuals. The populations has undergone a small increase of 1% per year over the last 5 decades.