Common Grackle – Quiscalus quiscula

A Glossy Black Bird With Iridescent Blue, Green, Purple and Bronze

© Rosemary Drisdelle

Sep 14, 2009

Common Grackles, Quiscalus quiscula, range throughout the United States and Canada, except in the far north. They are rare west of the Rocky Mountains. Plain and black from a distance, Common Grackles are beautiful birds close up when sunlight is reflected off their plumage. Coloration varies regionally—the birds are described as iridescent glossy green, blue, or purplish about the head and neck, and coppery, bronzed, or variably colored on the rest of the body. Adult Common Grackles have pale golden eyes and an intent, almost stern-looking gaze.

One of the icterids (taxonomic family Icteridae), Common Grackles are related to blackbirds, cowbirds, meadowlarks, and orioles, among others. They are the most common of three species of grackle found in North America. Key identification features include the pale eye, sturdy bill, and long tail (but other grackle species, the Great-tailed Grackle and the Boat-tailed Grackle, have longer tails).

Diet and Feeding Habits of Common Grackles

A mixture of plant and animal foods make up the diet of the Common Grackle. The birds prefer to feed on the ground, and eat invertebrates such as insects, insect larvae and worms that they find in the soil. They’ll also eat small vertebrates including fish and baby birds, as well as seeds, nuts, and even human garbage. Common Grackles often visit feeders, where they monopolize bird feed and prevent other birds from eating it. They have long been accused of damaging corn crops, though they may actually be more interested in eating insect pests of corn such as cut worms and corn borers, than they are in the corn itself.

Nesting and Breeding of Common Grackles

Though it's not unusual to see a solitary grackle, Common Grackles tend to feed, rest, roost, and even breed in groups. Typically nests are built high up in evergreen trees:

1. The nest is constructed of various materials including grass, twigs, leaves, and even pieces of garbage. It is reinforced with mud and lined with softer grass or hair and fur.
2. The female lays between one and seven eggs, which hatch after about two weeks.
3. Fledglings are ready to leave the nest after about another two weeks.
4. Young Common Grackles are plain brown birds with dark eyes.

Conservation Status of Quiscalus quiscula

According to the International Union for Conservation of Nature and Natural Resources (IUCN), there are almost 100 million Common Grackles in North America. National Audubon estimates are lower at just over 70 million, and survey data indicates the population is in decline, At present, Quiscalus quiscula is not a species of conservation concern.

Interesting Facts About the Common Grackle

Here are some things most people don't know about the Common Grackle:

• This species has a hard ridge in its upper beak that allows it to break into hard food items such as acorns.
• Common Grackles are often observed anting, and will also treat their feathers with surprising substances such as citrus oils, marigold blossoms, even moth balls.
• Small groups of Common Grackles nest communally inside the nests of raptors, particularly ospreys. The grackle nests are located under the rim of the osprey nest among the mass of twigs and sticks. These nests are ideally situated for the adult grackles to steal food from the ospreys.
• Common grackles sometimes nest in bird houses, in buildings, and in other cavities.
• During the winter months, most Common Grackles migrate to the southeastern United States, though a few remain all year round as far north as Nova Scotia, Canada. Winter flocks, which forage and roost together, may comprise thousands of birds.
• Flocks of Common Grackles often include a few individuals of other less common species. Look for various other species of blackbird.

Sources

“Common Grackle.” The Cornell Lab of Ornithology. www.allaboutbirds.org

Smithsonian Field Guide to the Birds of North America Floyd, Ted. New York: HarperCollins; 2008.

The IUCN Red List of Threatened Species. International Union for Conservation of Nature and Natural Resources. www.iucnredlist.org

“#14 Common Bird in Decline: Common Grackle.” National Audubon Society. www.audubon.org

A Common Grackle With its Pale Striking Eye

Common Grackle

Common Grackle With Blue and Copper Iridescense

Print Article

View All Articles

How to subscribe to feeds