Common Grackle
(Quiscalus quiscula)
Cool fact: 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 Grackle’s range continues to expand west, where it inhabits the trees planted in shelter belts. Common Grackles by Larry McQueen

Listen to a recording of a Common Grackle from
the Library of Natural Sounds:

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.

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).

Recording credits:
Common Grackle recording by Arthur A. Allen, LNS catalog number 12664.

Copyright© 1999 Cornell Lab of Ornithology

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Common Grackle (15133 bytes)