The Common Grackle is a small to medium-sized passerine bird that looks a bit stretched and has a predominantly black plumage. It is taller compared to a typical blackbird, and has a longer tail, longer and more tapered bill, and glossy-iridescent body. It is quite widespread across North America.
Common Grackles are big, clumsy blackbirds with long legs and tails. Their bodies grow to a length of 11 to 13 inches and their wings span about 14 to 18 inches across the wings. Their weight range is from 2.6 to 5 ounces. With this body size, they are comparably larger than the Red-winged Blackbird, and approximately of the same size as the Mourning Dove.
Common Grackle Birds have a flat head. And their slightly down curved bills are longer compared to most other blackbirds. They have expressive, bright golden eyes that capture the interest of its watchers.
When observed from afar, Common Grackles appear black. However, up close, they exhibit a glossy purple head that stands in contrast with their bronzy-iridescent bodies. Specifically, the feathers in the head appear black, with purple, green or blue iridescence, while the body plumage has a primary bronze sheen.
Male Common Grackles are a bit larger compared to females. They are also slightly glossier than their female counterparts. Moreover, their tails are longer and display a longitudinal ridge in flight.
Juveniles, on the other hand, have a dark brown plumage and a dark eye.
Distribution and Habitat
Common Grackles are frequently observed in human landscapes such as lawns, feedlots, city parks and fields. They use scattered trees for nesting and open ground for foraging.
They also do well in high trees, which are usually evergreens. On top of that, they are quite widespread in open habitats such as woodland, forest edges, meadows, and marshes. And during winter, they would forage and roost in big numbers with numerous varying species of blackbird. As a matter of fact, the only places that have few occurrences of Common Grackles are unbroken tracts of forest.
Their breeding habitats are the open and semi-open areas across North America east of the Rocky Mountains. They are considered permanent residents in most of their range. Northern birds move in groups to the southeastern United States.
The diet of Common Grackles varies, although seeds make up majority of it, especially agricultural grains like corn and rice. Seeds such as sunflower seeds, acorns, treat seeds like sweet gum also make up the list. Others would be wild and cultivated fruits and crops to nearly anything else, including garbage.
Because of its omnivorous nature, it also eats insects, frogs, small birds and mice. They are known as food stealers, and would just wait for someone to drop some food so that they could grab it immediately.
Common Grackles dominate smaller birds at feeders, eating scattered seeds at the ground.
Common Grackles are social animals. As a matter of fact, they are often found in groups, flying or foraging on their different habitats. They use their long legs in pecking for food rather than scratching.
When they are resting, they would sit in high tree branches or telephone lines and create unique sounds. They are also known to practice “anting” – wherein they would run insects on its feathers to apply liquids secreted by the insects.
During flight, the long tails of Common Grackles trail behind them, sometimes folded down the middle to form a V shape. Their wings seems short to the tail. Their flight is direct, with stiff wing beats.
Their songs are different depending on the season. For instance, during normal breeding seasons, they would create simple ‘chewink chewink’ sound, but as the season goes more complex, their calls also gets faster and faster.
Their nest is a well-covered cup in dense trees or shrubs that are close to water bodies. Sometimes, they will put their nest in cavities or in man-made structures. Most of the time, their nests are structured in colonies, with some of them being quite large. The completed nest is about 6 to 9 inches across, with an inside diameter of 3 to 5 inches and a depth of 3-9 inches.
The average size of the female’s clutch is 4 to 7 eggs. The incubation period for these eggs spans from 11-15 days. And the nestling period would range from 10 to 17 days. In average, the female raises about 1 to 2 broods in 1 year.
The Common Grackle is classified under the ‘Least Concern’ category of the IUCN Red List. It has a stable population and is quite widespread across its breeding range, although the North American Breeding Bird Survey estimates that the species’ populations have decreased by approximately 1.5 percent per year since 1966.
The estimated global breeding population of the species is 61 million, with 10 percent breeding in Canada and the rest being residents of the United States. It ranks 8 out of 20 on the Partners in Flight Continental Concern Score, and is listed by the 2014 State of the Birds Report as a ‘Common Bird in Steep Decline’.