Saturday, March 13, 2010
More on the Black-capped Chickadee
When we begin to hear the chickadee’s “phe-be” in early spring, it is like hearing an overture to a great natural musical revue, a concert which will go on for months as dozens of species sing for their mates.
Our Black-capped Chickadee is a songbird. When it sings - most frequently in the spring and summer - it sings this simple “phe-be” phrase. The song sounds very similar to the repetitive “phoe-be” of the Eastern Phoebe; the phoebe’s “phoe-be” is more explosive, not as sweet or high-pitched, and repeated over and over and over. The phoebe usually does not return to our neighborhoods in southeastern Vermont until very late March or early April. Most of my home records first list it during the first week in April.
Bird songs are closely connected with the breeding season. A male claims his territory and sings. His song is intended to impress the females, to warn other males away from his territory, and perhaps to draw predator attention to himself and away from the vulnerable female who is incubating or tending young. Later in the summer, songbird singing is more difficult to explain; then the young males are learning their songs.
That being said, the courtship rituals of our Black-capped Chickadee are very limited. Though often overlooked in our casual observations, many species have very precise rituals for attracting a mate. The Red-winged Blackbird flashes his bright red epaulets as he “sings” atop the reeds. Grackles spread their tails and flair their wings on tree branches. Brown-headed Cowbirds strut with their heads held high. Evening Grosbeaks crouch on the ground with tail spread and wings fluttering. Jays and cardinals often feed their mates. This is just the briefest sampling of courtship rituals.
The chickadee courtship ritual consists of the male chasing the female. I have stood in my backyard in early April and watched four or five chickadees in loud and noisy pursuit. I presumed there were males pursuing females, males trying to chase off rival males, males and females grabbing a quickie, and who knows what else.
Here is a description from Bent: “the birds grow agitated late in March and increase their vivacity during April and early in May. They hurry between aisles of trees and swerve over bypaths, and males dart at and even clasp one another. Then they part, and the more dominant male pursues and chases a female over brush piles and even to the ground. Then up they arise and hurry onward. A few such days of immoderate activity, and their nuptial rites seem completed.”
Forbush described the male Black-capped Chickadee as a “devoted father, assisting his mate in all the tasks of home-building, incubation and the raising of their offspring; and the birds exhibit a tender affection and constant solicitude for the care of their eggs and young.” Forbush was describing what scientist now term “social monogamy,” where a pair cooperates closely in the whole process of raising young.
Eventually a socially monogamous pair will raise a brood whose individual parentage is diverse and can only be deciphered by DNA analysis.
Forbush offers this summary of our chickadee: “The little Black-capped Chickadee is the embodiment of cheerfulness, verve and courage. It can boast no elegant plumes, and it makes no claims as a songster, yet this blithe woodland sprite is a distinctive character, and is a bird masterpiece beyond all praise.”
No argument there. With the chickadees in our woods and neighborhoods, we are assured of good birding.