Eastern Kingbird

The Eastern Kingbird is an aerial hawking insectivore of open spaces found in most regions of North America and well known for its conspicuous and aggressive nature. Indeed, Tyrannus means “tyrant, despot or king,” in reference to it’s genus’ aggressive defense of nests and mates, and their domination of other birds. It breeds throughout North America with the exception of northern Canada and the southwestern US. It winters in South America primarily in western Amazonia.

Adult Male (spring/summer)

Adult Male (spring/summer)
Head is black with an orange-red crown stripe, which is normally concealed. The chin is white; breast shows faint wash of gray, and, belly and undertail coverts white. Nape, back, rump and uppertail coverts are dark charcoal gray. Wings are black with white feather edging. Tail is black with white band along tip. Beak, legs and feet are black.

Adult Female (spring/summer)

Is similar but the decurved bill is shorter.

Juvenile (spring/summer)

Juvenile similar to adult, but shows buffy edges to wing feathers and a narrower white tip to tail. Also lacks the concealed crown patch.

General:

Large conspicuous black and white flycatcher. Length: 19-23cm. Wing: 33-38cm. Weight: 33-35grams.

Behaviour:

The Eastern Kingbird is usually solitary or in small family groups on breeding grounds. They often perch conspicuously atop trees, shrubs or man made objects like utility polls or wires. Flight is very characteristic with very shallow wing beats and raised head usually accompanied by metallic, sputtering calls. They are very aggressive to species threatening their breeding grounds and will attack any raptor no matter the size. They are visual hunters sallying out from perches to snatch flying insects. Characteristic posture and the shape of the head can often distinguish sexes. Males tend to perch very upright and to maintain a slight ‘crest’ by raising contour feathers of the crown. Agitated females also raise their crown feathers but normally perch in a more horizontal plane and maintain a round shape to the head.

Habitat:

The Eastern Kingbird can be found in semi-open habitats with a mix of grassy fields and trees like open yards, fields, pastures, grasslands or wetlands. It is abundant in open places along forest edges or water.

Information:

Despite its common name, the Eastern Kingbird breeds abundantly west of the Mississippi River, and its range extends to the Pacific Ocean. In the Great Plains and Far West it may breed sympatrically with 1 or 2 other species of kingbirds. Clutch size varies geographically, 2-5 pale with ring of reddish spots eggs, but females raise only a single brood per season. This low productivity is likely related to the species’ foraging habits and reliance on flying insects for food. Fly catching is an exacting mode of foraging, and individuals appear to have a difficult time feeding large broods adequately, especially when cool, wet weather reduces the availability of flying insects. The extended period of post-fledging parental care (3–5 weeks) appears to limit parents to a single brood per year.

Similar species:

Eastern Phoebe, Eastern Wood-Pewee, Black Phoebe, Western Kingbird.

Conservation Status:

Listed as Least Concern. However, numbers decreased by 41% between 1966 and 2010 according to North American Breeding Bird Survey.

Capture Rates

Eastern Kingbirds breed regularly at Colony Farm yet numbers are not high. They are long distance migrants as seen by capture rates peaking in June, July and August then absent from October through May.

Molt Summary:

PF: HY/SY incomplete/complete?; PB: AHY/ASY complete; PA partial (Mar-May)

Preformative molt apparently is nearly complete (including pp covs?) although innermost 1-2 pp and 1-2 ss (s1-s6) occasionally can be retained.

PAs include 0 – 4 inner gr covs and usually 1 – 3 terts but no central rects

Much is still not known of molt patterns in this species.

This HY bird in September is showing very fresh juvenal wing feathers. Notice also the thinner, more tapered outer primary coverts compared to the adult below.