I have developed a fascination and a deep respect for the Great Tailed Grackle as a result of making regular visits to Walmart. I began feeding these birds bread crumbs this winter because I like them so much and because I wanted to observe these clever characters hopping about dodging automobiles and people who apparently don’t have much use for them. Some always hang out on the roof with the fake owls that were put there to scare them. I wonder how many people have actually looked at the Great Tailed Grackle because both sexes are quite stunning. The male is glossy black with an ecclesiastical purple iridescence. He has a long, keel-shaped tail, massive bill and yellow eyes. The female is about half the size of the male and looks as if she’s been dipped in brown oil; she has a smaller keel shaped tail. The visual characteristic that stands out the most to me is the brilliance of those bright yellow eyes. These birds radiate intelligence! And, in fact, studies that have been done on these birds reveal that they are adept at problem solving (even from a human point of view). For example, the Grackles problem-solving power was tested by posing glass cylinders full of water with bits of food floating just outside the birds reach. To grab the morsels, the birds had to drop in pebbles to raise the water levels. After a number of trials most of the Grackles figured out that dropping pebbles into the water raised the water level so they could feed. They also learned that it was usually more efficient to use heavy pebbles to reach the snack, but if provided with too large stones the birds turned back to small pebbles to reach their goal. Another test done had even more dramatic results. Silver and gold tubes of food were presented to the grackles but only the gold tubes had peanuts and bread in them. The Grackles immediately chose the gold tubes, but when the food was placed in silver tubes the birds instantly chose them. These tests reveal not only problem solving ability but also the birds’ flexibility in terms of learning. Its important to note that Grackles outperformed three species in the crow family (Corvids). This desert-adapted bird doesn’t need much beyond food, trees, water, and its own wits for survival. Once confined to Central America, the species began moving north 200 years ago, and now covers an immense region from northwestern Venezuela up to southern Canada. In 1900, the northern limits of its range barely extended into Texas; by the end of the century it had nested in at least 14 states and was reported in 21 states and 3 Canadian provinces. This explosive growth occurred mainly after 1960 and coincided with human-induced habitat changes such as irrigation and urbanization. Where people have gone, Great-tailed Grackles have followed: you can find them in both agricultural and urban settings from sea level to 7,500 feet that provide open foraging areas, a water source, and trees or hedgerows. 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. Great-tailed Grackles are loud, social birds that can form flocks numbering in the tens of thousands. Each morning small groups disperse to feed in open fields and urban areas, often foraging with cowbirds and other blackbirds, then return to roosting sites at dusk. This evening routine includes a nonstop cacophony of whistles, squeals, and rattles as birds settle in for the night. As near as I can tell Grackles forage almost anywhere and will eat almost anything. What this says to me is that these kinds of birds have learned to co – habit with humans in very ingenious ways that must include being able to deal with pesticides. During the last month (March) I have noted that there are fewer Grackles hanging around the parking lot. One reason for this absence may be that during the day some birds are moving into more rural areas to feed. In addition to country foraging and prior to actual nesting, both males and females begin to collect material for the nest site about four weeks before actual breeding begins in April. Nesting occurs in colonies of a few to thousands, with the nests often placed close together. The actual nest construction is done after this period of “gathering,” which although not mentioned in any of the sources I consulted, must be related to the mating process. The females choose the nest site, and often “borrow” nest-building materials from other females. The nest is made of grass, twigs, reeds, and mud and is woven by the female in about 5 days in a tree, shrub, or hidden in marshland vegetation placed anywhere from 3 to 30 feet off the ground or water. Nest size varies from four inches across to 13 inches deep. The female will lay 4 to 7 eggs that are pale greenish brown with blotches. The young are ready to fledge in a month. Mother is responsible for brooding and feeding. During this period some male Grackles may guard the nest while the female forages. In contrast some others may pair with a second female during this time leaving the female to manage on her own. Curiously, fewer male than female nestlings survive. Adult male survival may also be lower than adult female survival, which would result in a female-biased adult sex ratio. Although there is considerable overlap in the distribution of the three species, the Common Grackle occurs throughout the eastern United States and Canada, the Great-tailed Grackle is found in the Midwest and south/western United States, and the Boat-tailed Grackle is confined to Florida and coastal areas of the Gulf states and the eastern United States. The Grackle is protected by the Migratory Bird Treaty Act, which as far as I can tell, means practically nothing. People routinely haze, shoot, or use pesticides to eliminate these birds but their numbers continue to increase. In this time of great uncertainty due to Climate Change and continued overuse of lethal pesticides I can’t help but feel reassured that some non – human species will survive, and whenever I spend time with the Walmart birds I feel flickers of hope rising. I am already looking forward to seeing the Great Tailed Grackles once again flooding the Walmart parking in Espanola by the middle of May.
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