Bell's vireo

Vireo bellii

Photo by Paul L'Etoile (Mango Verde)

Common name:
Bell's vireo (en); juruviara-de-Bell (pt): viréo de Bell (fr); vireo de Bell (es); braunaugenvireo (de)

Taxonomy:
Order Passeriformes
Family Vireonidae

Range:
This species is found breeding in the central and southern United States, from North Dakota to Ohio, south to Louisiana and Texas and also in southern Arizona, New Mexico and California, and into northern Mexico. They migrate south to winter along the Pacific coast of Mexico, Guatemala and Honduras.

Size:
These birds are 11-13 cm long and have a wingspan of 18 cm. They weigh 7-10 g.

Habitat:
The Bell's vireo is mostly found in low dense scrublands and woodlands, especially in riparian vegetation along rivers and streams, but also in dry scrublands, coastal chaparral and forest edges, from sea level up to an altitude of 2.000 m.

Diet:
They forage on low vegetation, mainly taking insects such as caterpillars, stink bugs, wasps, bees, beetles, grasshoppers and weevils, and also some spiders and a few berries.

Breeding:
Bell's vireos breed in April-July. They are monogamous, but may switch mates between successive nesting attempts within the same season and between years. The nest is an open cup made of stems, plant fibres, leaves, paper and strips of bark fastened with spider silk. The outside may be ornamented with spider cocoons and the inside is lined with fine grass. The nest is suspended from a low branch of a small tree or scrub. The female lays 3-5 white eggs with brown or black spots, which are incubated by both parents for 13-15 days. The chicks are fed by both parents and fledge 10-13 days after hatching, but only become independent 2 weeks later. They raise 1-2 broods per season.

Conservation:
IUCN status - NT (Near-Threatened)
This species has a relatively large breeding range and a global population estimated at 1,5 million individuals. The population has undergone a large decrease of 24% per decade over the last 4 decades, main caused by the loss of riparian habitats through agricultural, logging and housing developments.