Wood Warblers

It is still early spring in northern Illinois, and wood-warblers, in the family Parulidae, are starting to migrate through our area.  Noted for their bright breeding plumage, these small songbirds display a variety of colors from bright yellows to deep blues and greens with occasional flashes of orange and red.  For Spring Bird Count, always the first Saturday in May, an average of 30 species will be observed in Illinois.

Warblers migrate mostly at night, and will wait for favorable, southerly winds to fly.  During the day, they rest in tall trees, favoring oaks and willows, while feeding until the next available night for migrating.  Most species are insect eaters and require food several times during the day to supply the energy needed for migration.  Some may supplement their meals with seeds and nectar when available.

Warblers sing a wide variety of songs that are unique for each species, assisting in identification.  Songs are used for establishing territory and attracting mates.  Songs are mainly sung by males, although female songs have been documented.  One set of songs is sung mainly during the day for attracting mates, and they are relatively simple tunes.  A second set of songs, with a much more complex structure, is used for defending territory.  These are usually only heard early in the morning.

Several well-known observation spots are located in our area.  Some that you may find interesting include Illinois Beach State Park, Zion; Montrose Harbor and the Magic Hedge, Chicago; Midewin National Tallgrass Prairie, Wilmington; and Elsen’s Hill in West DuPage Woods Forest Preserve, Winfield.  You can attract them to your own backyard by planting native trees and shrubs, especially oaks.  Be sure to have a shallow dish or birdbath with plenty of water available.

Additional information is available from several online resources.  For identification of common species seen in northern Illinois, view Chicago Field Museum Field Guide 999 .  To find out what species are currently being observed and their locations, check out the Illinois Audubon Migration Dashboard .  Look for quick flashes of color among trees and shrubs, and listen for beautiful trills and melodies as you are out walking this spring.