The Yellow Warbler is a fascinating New World warbler species, which can be found in temperate North America, as far south as Central Mexico. This bird is known for its striking yellow coloration, covering its tail to forehead. In fact, it is considered the yellowest North American member of its species. There are three main groups of Yellow Warbler, divided into 35 subspecies. Interestingly, all subspecies look very similar, with the only difference being in males when in breeding plumage. Some of the subspecies are defined by the male’s head color in the breeding season, such as the Mangrove Yellow Warbler, which has 12 subspecies of its own.
When it comes to the Yellow Warbler’s physical appearance, it is a greenish-yellow on its upper parts with a bright yellow below. The eyes and beak are dark, while the feet are a lighter or darker olive. Females are somewhat duller, especially on their heads. Immature birds all have similarly greenish-yellow uppersides and are a duller yellow color below.
These birds prefer brushy habitats near water and are often seen foraging in shrubs, fairly low to the ground. In this environment, they feed primarily on insects and spiders, with some more northern species also eating some berries.
Breeding season for the American yellow warbler starts in May – June. During this period, they build a cup-shaped nest made out of twigs and grasses. An average clutch of 3 to 6 eggs is laid, with incubation taking around 11 days. Once hatched, young usually take around 75 days before they are fully-fledged, however, it has been recorded to take as little as 45 days.
Despite some populations being in decline due to habitat destruction, overuse of herbicides and pesticides, as well as grazing, this species is generally common. Having such a wide range, the Yellow Warbler is not considered under any immediate threat.