This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the Cassin’s kingbird.
Most of the species in the tyrannus genus are commonly called kingbirds, known to defend their nesting territories aggressively, attacking much larger predators, including hawks, crows and squirrels, that venture too close to the nest. This kingbird, tyrannus vociferans, as the name suggests, is not only aggressive, but is also loud.
The male Cassin’s kingbird will often sing at night and may start his “dawn song” at 3 a.m. Males and females greet each other by calling, fluttering wings and spreading tails. Males will perform a dance in which they call loudly while flying straight up, then stop and fall in a twisting flight down.
Although these birds are found in diverse habitat types with open areas for feeding and trees for nesting, in Colorado they most commonly use pinon-juniper areas for breeding. Their summer range in the United States extends from southern Montana through much of the southwest and also includes southern California. They winter in Mexico, where a large segment of the population remains year-round.
These large flycatchers perch on wires or tree branches to spot and capture insects in flight or on the ground. They will also hunt while hovering. In season, they will consume large quantities of fruits. They are not known to drink water, fulfilling this requirement only from the food they eat.
Cassin’s kingbirds have dark gray heads, throats and upper breasts, white chins and yellow bellies. Western kingbirds are a paler gray color, but otherwise similar, and the two are difficult to tell apart.
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