Wednesday, January 29, 2014

Cooper's Hawk

Cooper's Hawk
Cooper's Hawk was first described by French naturalist Charles Lucien Bonaparte in 1828. It is a member of the goshawk genus Accipiter. This bird was named after the naturalist William Cooper one of the founders of the New York Lyceum of Natural History  in New York. Other common names Big Blue Darter Chicken Hawk, Hen Hawk Mexican Hawk, Quail Hawk Striker and Swift Hawk.The average size of an adult male ranges from 220 to 410 g  with a length between 35 and 46 cm . The adult male is significantly smaller than the average female, which weigh 330 to 700 g  and measure 42 to 50 cm  long. Its wingspan ranges from 62 to 94 cm .Individuals living in the eastern regions, where the sexes average 349 g and 566 g  tend to be larger and heavier than those in the western regions, where the respective sexes average 280 g and 440 g  Cooper's Hawks have short rounded wings, the wing chord measuring 21.4-27.8 cm  long and a relatively long tail, 17-20.5 cm  long, with dark bands, round-ended at the tip. As in most Accipite the tarsus is relatively long measuring 5.6-7.6 cm 00 long, and the bill is relatively small with the Cullen from the ere measuring only 1.5-2.1 cm  Adults have red eyes and have a black cap with blue-gray upper parts and white underparts with fine, thin, reddish bars. Their tail is blue gray on top and pale underneath, barred with black bands.Immature have yellow eyes and have a brown cap with brown upper parts and pale underparts with thin black streaks mostly ending at the belly. Their tail is brown on top and pale underneath, barred with dark bands. The eyes of this hawk, as in most predatory birds, face forward, enabling good depth perception for hunting and catching prey while flying at top speeds. They have hooked bills that are well adapted for tearing flesh of prey.Immature are somewhat larger than a Sharp-shinned Hawk and smaller than a Northern Goshawk though small males nearly overlap with large female Sharp-shinned Hawks, and large female Cooper's Hawks nearly overlap with small male Goshawks. Although the coloration is generally somewhat similar between Sharp-shinned Hawks and Cooper's Hawks Cooper's appear broader-chested and larger headed, with generally more robust features. The crow-like size of Cooper's Hawks is sometimes distinctive from the Sharp-shinned but this can be less reliable in large female Sharp-shinned. Goshawks are usually more distinctive in their larger size and differing plumage markings, with the juvenile Goshawk having broader, darker streaking below with more irregular patterns than the immature Cooper's. The Cooper's Hawk appears long-necked in flight and has been described by birdwatchers as looking like a "flying cross" The Cooper’s Hawk is seen mostly flying with quick consecutive wing beats and a short glide though they may also soar


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