American Yellow Warbler

The Yellow Warbler (Setophaga petechia) is a vibrant member of the New World warbler family, Parulidae. It is the most widespread species within the diverse genus Setophaga, with a presence that spans across North America, the Caribbean, and parts of South America. The male in breeding plumage is a sight to behold, with brilliant yellow underparts and a greenish-golden back. Some males may exhibit rusty-red streaks on the breast and flanks, a nod to the species' scientific name which translates to "liver spotted."

Identification Tips

Adult Yellow Warblers are small, ranging from 10 to 18 cm in length, with a wingspan of 16 to 22 cm. They weigh between 7 and 25 grams, with an average weight of about 16 grams. The summer males are particularly striking, being the most yellow of warblers in their range. They have blackish olive wings and tail feathers with yellow edges, dark eyes, a short thin beak, and olive-buff feet. Females and non-breeding males are duller, especially on the head.

Habitat

The Yellow Warbler is found in a variety of habitats, including riparian woodlands, moist forests, mangrove swamps, shrublands, farmlands, and forest edges. They are also known to frequent suburban areas, orchards, and parks.

Distribution

This species breeds throughout temperate North America, as far south as central Mexico, and winters from southern California to the Amazon region, Bolivia, and Peru. The mangrove and golden warblers, subspecies of the Yellow Warbler, are found further south, reaching the northern Andes.

Behaviour

Yellow Warblers are territorial during the breeding season, often seen chasing away conspecifics. They migrate to wintering grounds as early as July, with most departing by the end of August. They forage by gleaning in shrubs and on tree branches, and by hawking flying insects.

Song & Calls

The Yellow Warbler's song is a melodious series of sweet notes, often transcribed as "sweet sweet sweet, I'm so sweet." Calls include a soft "chip" or a harder "ship," with a "seet" call possibly serving as an alert to cowbird presence.

Breeding

Breeding takes place in May or June for the American Yellow Warbler, with the nest being a sturdy cup in a tree. The female is more involved in nest building and incubation, while the male primarily forages for food. The clutch size ranges from 3 to 6 eggs, with incubation lasting around 11 days.

Similar Species

The Yellow Warbler can be confused with other yellowish warblers, but its extensive yellow coloring and reddish streaks on the males help distinguish it.

Diet and Feeding

The diet consists mainly of caterpillars, wasps, mayflies, moths, mosquitoes, beetles, damselflies, treehoppers, and spiders. They play a crucial role in controlling pest populations, particularly in agricultural areas.

Conservation Status

The Yellow Warbler is classified as Least Concern by the IUCN. While generally common, local declines due to habitat destruction and pollution have been noted. Conservation efforts focus on habitat protection and recovery, particularly for riparian areas.