Warblers and gnatcatchers are among the migratory songbirds arriving in Houston for fall© Kathy Adams Clark, Kathy Adams Clark/KAC Productions
Orange-crowned warblers and other autumn migrants have begun to arrive in area neighborhoods and yards.
Istroll through my densely wooded neighborhood at dawn as the earth awakens to the chittering, chattering and singing of chickadees, titmice, cardinals and other songbirds. Thier melodies greet the coming of a new day.
After decades of listening to songbirds with varied vocalizations, I know their names by their voices as easily as I know my children, grandchildren, friends and, yes, my wife by their voices. Recently, I’ve heard the voices of migratory songbirds arriving from northern breeding grounds to spend the winter here or to rest before heading to ancestral winter homes south of the border.
The brief, chip-chip vocalization of a Tennessee warbler that breeds across Canada and bordering U.S. states caught my ear. The bird didn’t stay long because it was hurrying to southern Mexico and Central America for the winter.
But when I heard the unique chipping notes of an orange-crowned warbler, it was like hearing an old friend from northern breeding grounds spending every winter in my yard.
Bird migration is mind-numbingly complex. Simply stated, autumn’s migratory songbirds undergo hormonal changes induced by dwindling daylight and the sun’s position in the sky that impel them to migrate southward.
Neotropical songbirds that breed in many parts of North America usually migrate to ancestral tropical lands after the breeding season. Other migratory songbirds in North America travel to the southern tier of the continent, including the Houston region.
Migratory songbirds are insectivores, meaning their main diet depends on an ample supply of insects. But on more northern breeding grounds, bitter cold weather means insufficient insects. That explains why some migratory songbirds head to temperate southern climates like Houston, where insects abound during winter. But many neotropical songbirds are hard-wired to head to Latin American winter homes.
On my morning walks, I’ve routinely seen migratory songbirds, like orange-crowned warblers, that will remain in Houston area neighborhoods for the winter. But their winter plumage is a drab grayish green, rarely showing their signature orange crown. You can identify them by faint streaking on the underside.
Other migratory songbirds here for the winter include blue-gray gnatcatchers that breed in many parts of North America, including north Texas. They utter a scratchy bee-beee or cat-like zeee sound. Being incessantly curious, the birds will hop into view on a twig and cock their heads at me as if to say, “And who are you?”
Fall's migratory songbirds arrive in Houston
- Yellow-rumped warblers are among the more common insect-eating northern songbirds that migrate here for the winter.
- They used to be separated into two species, the myrtle warbler in the east and the Audubon’s warbler in the west, until studies found they were the same species.
- The “Audubon” variety generally breeds west of the Rockies, while the “Myrtle” variety typically breeds east.
- Yellow-rumped warblers begin arriving for winter residence in the Houston region in September and increase in numbers from October to early November.
- The bird has an unusual gastrointestinal system that enables it to digest wax myrtle berries, hence its original name, “myrtle warbler.”
- Look for the birds foraging among backyard trees and shrubs.
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