I feel a sudden whoosh within inches of my head while walking. The harsh caw I hear should have warned me about this predator. It is a grackle.
According to Wikipedia, grackle is the common name of any of eleven passerine birds native to North and South America. A passerine is any bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or songbirds, passerines are distinguished from other orders of birds by the arrangement of their toes — three pointing forward and one back — which facilitates perching.
There are many kinds of grackles:
· Boat-tailed grackle.
· Common grackle.
· Great-tailed grackle.
· Slender-billed grackle — extinct 1910.
· Nicaraguan grackle.
· Greater Antillean grackle.
· Carib grackle.
· Red-bellied grackle.
· Velvet-fronted grackle.
· Golden-tufted grackle.
· Colombian mountain grackle.
Sometimes members of the starling family have historically been called grackles. Tristram's starling is sometimes known as "Tristram's grackle," and the hill mynas have also been called grackles.
Common grackle
Description
Common grackle adults have a long, dark bill, pale yellowish eyes and a long tail; their feathers appear black with purple, green, or blue iridescence on the head, and primarily bronze sheen in the body plumage. Adult females, beyond being smaller, are usually less iridescent; their tails in particular are shorter, and unlike the males, do not keel — display a longitudinal ridge — in flight and are brown with no purple or blue gloss. Juveniles are brown with dark brown eyes. When grackles are in a group, they are referred to as a "plague."
Foraging and diet
The common grackle forages on the ground, in shallow water, or in shrubs; it may steal food from other birds. It is omnivorous, eating insects, minnows, frogs, eggs, berries, seeds, grain and even small birds and mice. Grackles at outdoor eating areas often wait eagerly until an unwary bird drops some food. They rush forward and try to grab it, often snatching food out of the beak of another bird. Apparently, they steal human sugar packets too as shown by the video above. Grackles prefer to eat from the ground at bird feeders, making scattered seed an excellent choice of food for them. Grackles can be regularly seen foraging for insects, especially after a lawn trimming.
Grackles have a unique adaptation in the keel within their bill which allows them to crack and cut hard nuts or kernels. It is used in a sawing motion to score open acorns or dried kernels. Large adductor muscle within their jaw also makes this adaptation even more useful for opening hard seeds and acorns.
Along with some other species of grackles, the common grackle is known to practice "anting," rubbing insects on its feathers possibly to apply liquids such as formic acid secreted by the insects.
Great-tailed or Mexican grackle
Description
According to Wikipedia, males are iridescent black with a purple-blue sheen on the feathers of the head and upper body, while females are brown with darker wings and tail. Adults of both sexes have bright yellow eyes, while juveniles of both sexes have brown eyes and brown plumage like females — except for streaks on the breast. Great-tailed grackles, particularly the adult males, have a keel-shaped tail that they can fold vertically by aligning the two halves.
Distribution and habitat
Great-tailed grackles originated from the tropical lowlands of Central and South America, but historical evidence from Bernardino de Sahagún shows that the Aztecs, during the time of the emperor Ahuitzotl, introduced the great-tailed grackle from their homeland in the Mexican Gulf coast to the Aztec capital of Tenochtitlan in the highland Valley of Mexico, most likely to use their iridescent feathers for decoration. In more recent times, great-tailed grackles expanded their breeding range by over 5,500% by moving north into North America between 1880 and 2000, following urban and agricultural corridors. Their current range stretches from northwest Venezuela and western Colombia and Ecuador in the south to Minnesota in the north; to Oregon, Idaho and California in the west; to Florida in the east, with vagrants occurring as far north as southern Canada. Their habitat for foraging is on the ground in clear areas such as pastures, wetlands and mangroves.
Diet
Great-tailed grackles are noted for their diverse foraging habits. They extract larvae and insects from grassy areas; eat lizards, nestlings and eggs; forage in freshly plowed land; remove parasites from cattle; and eat fruits (e.g., bananas, berries) and grains (e.g., maize, corn on the cob) by opening the husks. They turn over objects to search for food underneath, including crustaceans, insects and worms. They hunt tadpoles and fish by wading into shallow water. Although they do not swim, they catch fish by flying close to the water's surface and are even reported to dive a few inches into the water to retrieve a fish. They are also known to pick dead insects off the license plates of parked cars and kill barn swallows while flying.
Vocals
Great-tailed grackles have an unusually large repertoire of vocalizations that are used year-round. Males use a wider variety of vocalization types, while females engage mostly in "chatter," however there is a report of a female performing the "territorial song." Because of their loud vocalizations, great-tailed grackles are considered a pest species by some.
In culture
In Mexico, where it is known as the chanate or zanate, there is a legend that it has seven songs. "In the creation, the Zanate having no voice stole its seven distinct songs from the wise and knowing sea turtle. You can now hear the Zanate's vocals as the Seven Passions — Love, Hate, Fear, Courage, Joy, Sadness, and Anger — of life." Mexican artisans have created icons in clay, sometimes as whistles that portray the sea turtle with the zanate perched on its back.
In Colombia, the species is called Maria mulata, and is the official bird of Cartagena de Indias. Cartagena artist Enrique Grau had an affinity for these birds, and because of this inspiration, many Colombian monuments and artistic works were created in honor of the bird's intelligence, adaptability, cheerfulness, sociability, collaborative tendencies, diligence, craftiness and ability to take advantage of adversity.
In Austin, Texas, it is commonly found congregating near the city's numerous food trucks. The great-tailed grackle has become an icon in the city, especially on the campus of the University of Texas at Austin, to the extent that local radio station KUT offers grackle-themed socks as a popular gift for its supporters. However, Austin does not want the birds in its downtown area, so city employees use various tricks to make the birds move:
Grackles as pesky as crows
According to Cornell University, those raggedy figures out in cornfields may be called scarecrows, but grackles are the No. 1 threat to corn. They eat ripening corn as well as corn sprouts, and their habit of foraging in big flocks means they have a multimillion-dollar impact. Some people have tried to reduce their effects by spraying a foul-tasting chemical on corn sprouts or by culling grackles at their roosts.
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