| Species: Eastern Kingbird
Tyrannus tyrannis
Description:
Kingbirds are
aerial hawking insectivores of open spaces found in most regions of
North America and well known for their aggressive nature. Indeed,
Tyrannus means “tyrant, despot or king,” in reference to their
aggressive defense of nests and mates, and their domination of other
birds. Pairs are monogamous, maintain territories while breeding,
and if both survive to the following breeding season, usually remate
and reuse former territories.
Identification:
General: The
Eastern Kingbird is a large Tyrant flycatcher and a bird of fields
and other open areas. Despite its name, the Eastern Kingbird is a
common and widespread species found across north America from the
Atlantic to the Pacific coast.
Fairly large
flycatcher but 1 of the 2 smallest members of genus Tyrannus
occurring in North America. Total length 19.5–23.0 cm 8.5” long 40g.
. Identified by contrasting black upperparts and white underparts.
Upper chest marked by faint, dull grayish band. Dark black head
often slightly crested, especially in males. Concealed patch of
feathers on crown varies from orange to red, and sometimes yellow.
Plumage sexually monomorphic. However, 2 outer primaries (P9 and
P10) of males notched and attenuated, whereas only P10 of female
similarly notched and attenuated with extent of attenuation
considerable (including females with no notching) and should be
examined in relation to age. Sexual size dimorphism moderate; males
larger than females in some linear measures of size.
Adult Male:
The sexes can often be distinguished, however, by their
characteristic postures and the shape of the head. Males tend to
perch very upright and to maintain a slight “crest” by raising
contour feathers of crown. Agitated females also raise their crown
feathers, but normally perch in more horizontal plane and maintain
round shape to the head.
Adult female:
Same as adult male
Juvenile:
Juvenile similar to adult, but shows buffy edges to wing feathers
and a narrower white tip to tail. Also lacks the concealed crown
patch.
Similar Species:
Gary Kingbird Tyrannus dominicensis distinguished from Eastern by a
much larger bill, heavier body, longer tail and shorter wings.
Behavior:
The Eastern Kingbird overwinters in Amazonia and maintains different
social and feeding behaviors there than are seen during the breeding
season. Most individuals travel in flocks and forage on fruit,
returning to North America to begin laying eggs by late May and
early June.
Habitat:
Open environments usually breeds in fields with scattered shrubs and
trees, orchards, along shelterbelts, and especially along woodland
edges in forested regions. A “savannah species” but given suitable
nest sites and perches, will nest in many other habitats—e.g.,
desert riparian. Appears drawn to water; nesting densely in trees
that overhang water or in dead, standing snags surrounded by water.
In North America precolonial times may have been limited to swamps,
marshes, edges of lakes and rivers, and open, disturbed environments
(i.e., large forest blowdowns and forest fires).
Information:
Of the 8 species
that breed north of Mexico, the Eastern Kingbird is the most widely
distributed and is the only species to breed in eastern North
America. 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 (mode of 3–4 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.
Conservation
Status:
Although widespread
and common and currently listed as a species of least concern (LC)
recent data suggest populations may be declining.
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