Commonly Nesting Warblers

     Yellow warblers and common yellow-throats are adaptable species of warblers that commonly nest in the Middle Atlantic States, and throughout much of North America, but in different niches to reduce competition for space and food between them.  Both species spend northern winters south of the United States, the yellow warblers in Central America and northern South America and the yellow-throats in Mexico and Central America.  Both species arrive in this area toward the end of April and into early May to raise young.  And many of them leave North America early in September, mostly migrating south at night and eating invertebrates during the day between flights. 
     Warblers are a large family of small, colorful birds that probably originated in Central America.  But as the last ice age receded north about 10,000 years ago, many warbler species acquired the habit of pushing north each spring to find breeding areas free of competition for space and food from their relatives in Central America. 
     Warbler species have certain characteristics in common, demonstrating their common ancestry.  All of them are small.  Most kinds have yellow in their plumage.  Male yellow warblers and yellow-throats are attractive, with much yellow in their feathering.  And both these types of warblers, as all their kin, feed on small invertebrates, the reason why most species of their large family winter in sub-tropical  climates where invertebrates are active and available the year around.
     Yellow warbler males are almost completely yellow, like canaries, but with several rows of elongated, orange spots on their underparts.  Females of that species are a pale yellow all over.  Yet because of their small size and retiring habits, they usually are difficult to spot among the foliage of small trees.  Their songs are much more likely to give away their presence. 
     This species nests in most of North America, including well into Alaska.  They rear offspring mostly in areas of moist ground and young trees, especially willows, along waterways, wetlands and ponds.  Females place their petite nests of fine grasses, plant down and spider webs low in small trees and shrubbery.  To establish territory and attract a mate, each male repeatedly sings a lively "sweet, sweet, I'm so sweet" in a distinctive rhythm of notes.
     Male common yellow-throat warblers are striking in appearance.  They are olive-brown, with yellow throats, a black mask around the eyes and white above the mask.  Their mates are the same in appearance, except they don't have the mask or the white above it.  They are better camouflaged than the males to be less visible around their young.
     Yellow-throats nest in most of North America, south of Hudson Bay.  Their nesting niche is in expanses of thick shrubbery in hedgerows, woodland edges and clearings, and in older suburban areas that have lots of bushes.  Males sing a unique song that, with imagination, sounds like "witchety, witchety, witchety"..........  Like yellow warblers, this species is heard more than it is seen because its members stick tight to the sheltering shrubbery for their protection against predation.
     Watch for these beautiful warblers in North America during summer.  They help liven the niches they raise young in.