yellow warbler (en); mariquita-amarela (pt); paruline jaune (fr); canario del manglar (es); gold-waldsänger (de)
These birds breed throughout much of North America, including Alaska, northern Canada, and the northern 2/3 of the United States. They migrate south to winter in southern California, southern Florida, and south through the Brazilian Amazon, Bolivia, and Peru.
These small songbirds are 12-13 cm long and have a wingspan of 16-20 cm. They weigh 9-11 g.
They breed in moist, deciduous thickets, especially in willows, but also in shrubby areas and abandoned agricultural fields. In the winter they are found in mangroves, the edges of marshes and swamps, willow-lined streams, and leafy bogs.
Yellow warblers are predominantly insectivorous, gleaning insects and their larvae, and spiders from the vegetation. In winter they also eat berries.
They breed in May-June. The female builds the nest, a deep cup of grasses and bark, covered on the outside with plant down and fine fibers, lined with fur or fine plant fibers. It is placed in an upright fork of a scrub or tree. There the female lays 4-5 greenish white eggs with dark spots, which she incubates alone for 10-14 days. The chicks are fed by both parents and fledge 9-12 days after hatching, but parental feeding may continue for 2 more weeks.
IUCN status - LC (Least concern)
This species has a very large breeding range and a global population of 40 million individuals. The population is believed to be stable, but in some areas the loss of riparian woodland habitat and extensive parasitism by cowbirds affect this species. On the other hand, in areas where grazing and herbicide use are restricted, permitting regrowth of riparian vegetation, the species may be increasing.