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 Common
Grackle
Common Grackles occur
throughout the United States east of the Rocky Mountains;
in Canada, these grackles are found north to the latitude
of the Hudson Bay and as far northwest as northeastern
British Columbia. They usually nest in dense colonies
with as many as 10 to 30 pairs and occasionally a colony
will have more than 100 pairs. Common Grackles favor
conifers close to open areas and water as nest locations,
although a wide variety of sites-from open nests built in
clumps of marsh grass in Red-winged Blackbird colonies to
old woodpecker holes and the interior of barns-have been
observed.
Common
Grackle Range Map
Their diet consists of a wide variety of animal and
vegetable food, including insects and invertebrates but
also occasional eggs and nestlings. In rare instances,
Common Grackles will attack and eat small birds and
lizards, and in coastal areas they forage at the tide
line for small invertebrates, even wading into the water
to capture live fish. During the winter and migration
months, their diet shifts to plant food. Because of their
predilection for agricultural grain and seeds, especially
corn, Common Grackles have earned a reputation as a
significant pest in certain areas of North America. These
grackles feed in farm fields, pastures, and suburban
lawns by walking, rather than hopping, and they act
aggressively toward, even stealing food from, other
ground-foraging birds such as robins. A common display
for a male grackle includes fluffing the body feathers,
spreading its wings and tail so as to increase its
apparent size, vocalizing, and posing before a female
with its bill held vertical. The brief, unmusical song is
often described as sounding something like a rusty gate.
After the breeding season, Common Grackles form large
foraging flocks that often include other blackbirds and
cowbirds. Flock size increases as birds from the northern
part of the range migrate to winter destinations in the
southeastern United States, from the Carolinas to the
Gulf Coast. In flight, the flocks tend to be as broad as
they are long, unlike the long and cylindrical flocks of
Red-winged Blackbirds.
Description: Common Grackles are large,
iridescent blackbirds (11 to 13.5 inches in length), with
pale yellow eyes, a long, sharp black bill, and long
tails. The central feathers of the long, rounded tail are
often depressed, so that the tail is displayed in flight
with a deeply keeled V-shape.
Typically, females are about 12 percent smaller than
males and slightly less glossy. Young birds have brown
eyes that turn yellow during their first autumn. Although
they may appear to be all black, in good light Common
Grackles display a metallic sheen, the color of which
varies regionally. In the southeastern race (the Purple
Grackle) that is found from central Louisiana and Alabama
north to southern New York and Connecticut, the head,
back, and sides are purple, the back may show iridescent
barring, and the tail is usually blue green. Birds found
west of the Appalachian Mountains and in New England (the
Bronzed Grackle) have blue-green heads, a sharply defined
bronze back without iridescent bars, and a purplish tail.
The slightly smaller and nonmigratory Florida Grackle of
peninsular Florida and the Gulf Coast typically has a
purple head, dark green back, and blue-green tail. At one
time these races, or subspecies, were separated as
distinct species. Intermediately colored birds may be
found where these races meet.
Common Grackles can be distinguished from other similarly
sized all-black blackbirds with yellow eyes, which
include the Rusty Blackbird (Euphagus carolinus)
and Brewer's Blackbird (E. cyanocephalus), by
their larger size and proportionally longer tails and
bills. Neither Rusty nor Brewer's blackbirds have keeled
tails. Common Grackles fly in a straighter, less
undulating manner than other blackbirds. They are much
smaller and have proportionally shorter tails than
Boat-tailed and Great-tailed grackles (Quiscalus
major and Q. mexicanus).
Prior to the European settlers' arrival in America, the
Common Grackle, a semicolonial species found in open
areas with scattered trees, probably nested in cottonwood
and sycamore groves along watercourses in the Midwest.
But when forests were cleared to create agricultural
land, the Common Grackle began to increase its numbers,
such that now it is one of the most abundant breeding
birds in North America. Today, the Common Grackles
range continues to expand west, where it inhabits the
trees planted in shelter belts.
Visit Shaw Creek
Bird Supply to see our selection of Common
Grackle Feeders.
Copyright © 2003 Shaw Creek
Bird Supply
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