Kentucky warbler

Oporornis formosa

Photo by Brian Small (Larkwire)

Common name:
Kentucky warbler (en); mariquita-do-Kentucky (pt); paruline du Kentucky (fr); chipe cachetinegro (es); Kentuckywaldsänger (de)

Taxonomy:
Order Passeriformes
Family Parulidae

Range:
This species breeds in the eastern United States, from Wisconsin to New York and south to north-eastern Texas to northern Florida. They migrate south to winter in the Caribbean and from eastern Mexico to northern Colombia and north-western Venezuela.

Size:
These birds are 12-13 cm long and have a wingspan of 18-22 cm. They weigh 10-14 g.

Habitat:
The Kentucky warbler breeds in humid deciduous forests, dense second growths, and swamps, favouring forests with a slightly open canopy and a dense understorey. Outside the breeding season they are found in moist tropical forests. This species occurs from sea level up to an altitude of 1.850 m.

Diet:
They forage on the forests leaf litter and also on the lower parts of the trees and scrubs, taking insects, such as ants, bees grasshoppers and caterpillars, as well as spiders and sometimes seeds and fruits.

Breeding:
Kentucky warblers breed in May-July. The nest is a cup made of grasses, rootlets, plant fibres and dead leaves, usually hidden by overhanging vegetation or fallen branches, and built so that the base rests on the ground, sometimes partly anchored by a small scrub. There the female lays 3-6 white or creamy-white eggs with grey and brown blotches. The eggs are incubated by the female for 12-13 days. The chicks are fed by both parents and leave the nest 8-10 days after hatching, but only start flying some 4 days later and only become fully independent 2 weeks later. Typically, each pair raises a single brood per season.

Conservation:
IUCN status - LC (Least Concern)
This species has a very large breeding range and a global population estimated at 1,1 million individuals. The population has undergone a small decline over the last 4 decades, especially in the southern Appalachian region, but it is not considered threatened at present.