Yellow warbler
The Yellow Warbler is a small migratory bird belonging to the family of wood warblers, characterized by its bright yellow plumage and melodic "sweet, sweet, sweet" song. Measuring about four to seven inches (10 to 18 centimeters) in length and weighing just over half an ounce (14 grams), these birds are commonly found across North America during the breeding season, migrating from northern Canada to northern South America for the winter. Males are easily recognizable by their vivid yellow coloring and rust-colored streaks, while females sport a more subdued greenish back with faint streaks.
Nesting typically occurs in dense thickets or garden shrubbery, with females constructing cup-shaped nests from grass and plant fibers. Their breeding strategy includes a unique behavior involving the parasitic brown-headed cowbird, which often lays eggs in Yellow Warbler nests. Yellow Warblers primarily feed on insects, caterpillars, and spiders, playing a beneficial role in controlling pest populations. Despite facing threats from habitat destruction, their population remains stable, and these birds can live up to nine years, showcasing a complex life cycle that includes cooperative parenting and territorial behaviors.
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Yellow warbler
Yellow warblers are well-known birds which belong to the family of wood warblers. They are often called wild canaries because of their yellow plumage and loud "sweet, sweet, sweet" song. They are familiar birds which migrate between northern Canada and northern South America.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Parulidae
Genus: Setophaga
Species: Petechia
The yellow warblers are only four to seven inches (10 to 18 centimeters) long and weigh only a little over a 1/2 ounce (14 grams). Their wingspans are just a little greater than their body lengths, or six to nine inches (15 to 23 centimeters). Bright-yellow plumage, or feathering, covers most of the bodies of the males. On their upperparts they have greenish feathers, and rust-colored streaks run along their breasts and sides. The females are very similar to the males, but they have greener backs and only very faint rust-colored streaks if any at all.
Dense thickets and garden shrubbery are the most common nesting sites of yellow warblers. They appear to prefer willow and alder trees in damp places or cottonwood trees beside rivers. During the winter they live in Central and South America, but they then migrate north to the United States and Canada in order to breed between March and July. A male arrives first and chases other males from his territory. When a female arrives he tries to chase her away also. If he is unable to chase her away after three or four days, then he allows her stay, and they mate.
The female builds a cup-shaped nest of grass, cobwebs, and soft fibers from plants. She places the nest in the fork of a small sapling or shrub. Stealing nesting material from a neighbor in a nearby territory is a common nest-building practice among females. She incubates her three to six eggs for 11 to 14 days. During this time the male may mate with a second female in his territory. After the young hatch, both parents feed the young until they fly away three to four weeks after hatching. The young are then independent and leave their parents' territory. Shortly after this, the male and female also separate and migrate south again in the fall. Birds may live to migrate and mate until they are up to seven years old.
It is quite common for a brown-headed cowbird to lay her eggs in the nests of other birds such as the yellow warbler. She does this so that the other birds will incubate her eggs and raise her young. Female yellow warblers often lay a new lining in the nest which covers the eggs of the cowbird, and she may even bury some of her own brown-speckled, white eggs. She then lays a new clutch, or batch, of eggs and incubates them instead. The chicks in the other eggs fail to develop and die. Some nests may have several stories or layers because of this.
Yellow warblers eat caterpillars, insects and their eggs, and spiders and their eggs. They are helpful in eating a number of insect pests, such as cankerworms and "inchworms" which would grow into moths. Young gypsy moths and browntail moths are also frequent prey. Yellow warblers find all their food among the leaves, on tree bark, in the air, and even on the ground under fallen leaves. Snakes, foxes, and birds of prey are among the yellow warblers top predators.
The call of yellow warblers has been described as a ringing "sweet, sweet, sweet" and other high-pitched whistles.
The lifespan of a yellow warbler is up to nine years. Habitat destruction of southern breeding grounds is the greatest threat to these birds, although their population is not in serious danger.
Bibliography
Polan, Jason. “Yellow Warbler - Audubon Field Guide.” National Audubon Society, www.audubon.org/field-guide/bird/yellow-warbler. Accessed 16 Mar. 2024.
The Cornell Lab of Ornithology. “Yellow Warbler Identification.” All About Birds, 2024, www.allaboutbirds.org/guide/Yellow‗Warbler/id#. Accessed 16 Mar. 2024.