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about Blue Jay.....
(from: http://www.birds.cornell.edu/BOW/BLUJAY/
there are a sound file and several pictures of blue jays on the website.)
Blue Jay
(Cyanocitta cristata)
Cool fact: Infamous as a destroyer of eggs and nestlings, Blue Jays actually derive only a small percentage of their annual food needs from these sources. Its diet is mostly vegetarian, including especially acorns, beech nuts, and seeds. Blue Jays also eat a variety of animal foods including grasshoppers, beetles, caterpillars, and small vertebrates. Blue Jays are intelligent and adaptable, taking advantage of almost any food resource, and will readily take to back yard bird feeders. Nonmigratory populations of Blue Jays store food such as acorns in bark crevices or in the soil.
Listen to a recording of a Blue Jay from the
Library of Natural Sounds:
Blue Jay sounds [61k]
Common, conspicuous, and noisy, Blue Jays are capable of making a wide variety of sounds. In addition to the loud and often heard jay! jay! call, a bell-like tull-ull call, a melodious whistled teekle, and a variety of chattering, harsh notes and growls may be heard. Blue Jays also produce a remarkable imitation of the scream of a Red-shouldered Hawk.
When around the nest, Blue Jays become more quiet. The nest is usually situated between 8 and 20 feet up in a coniferous, or occasionally, deciduous tree. The nests of other passerines are sometimes appropriated by these jays. The female incubates most of the eggs, and she may be fed by the male while on her nest. Both parents bring food for the hatchlings. In late summer and fall, Blue Jays travel in small flocks and family groups.
The Blue Jay's range extends throughout deciduous forests, parks, and residential areas across eastern North America from Newfoundland to central Alberta, and south to Florida and eastern Texas. Mixed woodlands with oaks and beeches are preferred. The western edge of the range stops abruptly where the arid pine forest and scrub habitat of the closely related Steller's Jay (Cyanocitta stelleri) begins. Recently, the range of the Blue Jay has extended to the Northwest so that it is now a regular but still-rare autumn migrant along the northern Pacific Coast. The popularity of bird feeding is thought to have promoted an increase in the population of Blue Jays in the Northeast.
Northern populations migrate south, sometimes in large flocks of up to 250 birds. Typically, the noisy jays are quite noticeable, but Blue Jays tend to fly high and quietly during migration.
Description: Blue Jays are medium-sized (approximately 11 inches in length), colorful birds with crests. Their crown and crest are light violet-blue. Under the base of the crest and extending through the eyes across the forehead is a black band. Over the eye is a short white superciliary stripe; ear coverts, cheek, and throat are also white. Below the throat is a narrow black necklace that extends upward and connects behind the ear-coverts with the black head band. The lower breast, belly, and vent area are off-white.
The upper parts are bluish gray and brightest on the rump. The wings and tail are bright sky-blue with heavy black barring. The wings show a single, broad white wingbar as well as white-tipped secondary feathers. The corners of the tail are white also. Blue Jays are dull gray underneath the tail and wings, except for white feather tips. Their bill, legs, and eyes are all blackish. Both sexes are similar in appearance.
Steller's Jays and Blue Jays are the only North American jays with barring on their wings and tails. Both are crested, but the Steller's Jay has a dark, almost black, head and crest and lacks any white underneath.
Recording credits:
From the LNS production, Bird Songs of the Rocky Mountain States and Provinces.
Blue Jay calls recorded by Geoffrey A. Keller & Randolph Scott Little
Slides used are available from the Cornell Lab of Ornithology's Visual Services Department
Copyright?1999 Cornell Laboratory of Ornithology
Blue Jay
Blue Jay with nestlings
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哈哈哈哈 O(∩_∩)O哈哈~ 好久不来了，不小心看了一眼自己主页，发现自动关联了自己以往发过的帖，点进这个看了一眼，笑个半死。。。敢情我当初还发过这么搞笑的东西啊，我自己完全不记得了 
雷达卡
发表于 2007-4-26 18:50:33
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ps,师傅是否有危机感啊？ 
－－翠绿的蛇？唉，爬行的咚咚还是很恐怖 
发表于 2007-4-26 23:52:53
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