Great Tailed Grackle By Vicky Gomez Summer 2016
Name and General Characteristics •
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The Great Tailed Grackle can be identified by a its long, deeply keeled tail. Large, thick bill, with nearly straight culmen. Flat crown; shallow forehead. The adult male is entirely black with violet-blue iridescence. It has yellow eyes, and both the bill and legs are black. The adult female is smaller than the male. It has no keeled tail. She is brown above with dull iridescence on wings and tail; buffy on head and below, becoming darker brown on belly and vent. She has dark lateral throat stripes, and yellow eyes.
Adult female, male, and juveniles
Great tailed Grackle
Energy Transfer: Food Web The great tailed grackle is an omnivore, so it consumes both plants and animals. Its diet consist of grains such as corn, sorghum, and oats as well as fruits. Animal prey includes grasshoppers, beetles, spiders, bees, wasps, snails, worms, slugs, and moths. Grackles also feed on tadpoles, frogs, lizards, snakes, fish, and small mammals such as mice and shrews, as well as bird eggs and nestlings.
Ecology The great tailed grackle can be found in both agricultural and urban settings. In rural areas, look for grackles pecking for seeds in feedlots, farmyards, and newly planted fields, and following tractors to feed on flying insects and exposed worms. In town, grackles forage in parks, neighborhood lawns, and at dumps. More natural habitats include chaparral and second-growth forest. You’re unlikely to see them in dense forests, or in deserts or prairie habitats that lack access to water. The grackle is a predator because it hunts and eats other animals, but it can also become a prey for hawks, coyotes, and house cats if they can catch them.
Evolution •Great-tailed Grackles are loud, social birds that can form flocks numbering in the tens of thousands. •They have an evening routine that includes a nonstop cacophony of whistles, squeals, and gunfire-like rattling as birds jostle for preferred positions. •In early spring, males establish breeding territories in one or more trees, which they fiercely defend against other males. Dominant males mate with one or more “social mates” within their territory and may try and mate with other females. •Females brood and feed the chicks, which the male defends from intruders. •The grackle is seen and treated as a pet in most homes. Some people try to use repellants to keep them out of their lawns, but despite their efforts, the grackle population continues to grow.
https://youtu.be/fj1 cqIXJz6E https://youtu.be/T mLIPL0tSqo
Fun Facts •
In winter, enormous flocks of both male and female Great-tailed Grackles gather in “roost trees.” These winter roosts can contain thousands of individuals, with flocks of up to half a million occurring in sugarcane fields in Texas’s Rio Grande Valley.
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In 1900 the northern edge of the Great-tailed Grackle’s range barely reached southern Texas. Since the 1960s they’ve followed the spread of irrigated agriculture and urban development into the Great Plains and West, and today are one of North America’s fastest-expanding species.
Resources •
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Bibliography: Society, N. G. Great-Tailed Grackles, Great-Tailed Grackle pictures, Great-Tailed Grackle facts. Retrieved June 29, 2016, from http://animals.nationalgeographic.com/animals/birding/great-tailed-grackle/ In-line Citation: (Society, n.d.) Bibliography:Gunderson, B. Great-tailed Grackle. Retrieved June 29, 2016, from https:// www.allaboutbirds.org/guide/Great-tailed_Grackle/lifehistory#at_habitat Rambo. Bracken PowerPoint template. Retrieved June 29, 2016, from https:// www.presentationmagazine.com/bracken-powerpoint-template-10369.htm jason. (2011, August 30). Xenogere. Retrieved June 29, 2016, from http://xenogere.com/tag/great-tailed-grackle-quiscalus-mexicanus/