The Cooper's Hawk breeds mainly in the United States, southern Canada and northern Mexico. This species was named in 1828 by Charles Bonaparte in honor of his friend and colleague William C. Cooper. They are migratory birds that rely heavily on thermal air for direction. The female Cooper's Hawk is a third larger than the males, and this species is an excellent example of dimorphism. They are among the most reversed size dimorphisms among falcons in the world. They breed in forests and dense woods. They are also noted to live in suburban and urban habitats. They consume prey of various sizes, including birds and mammals such as doves, blackbirds, chipmunks, squirrels, and different rodents. By the mid-1990s, the eastern population of the birds declined significantly. The main causes of this population decline include trapping, pesticide contamination, pollution and shooting. Thus, the species is listed as threatened or endangered in some eastern states. Although their population was low, their recovery is now slowing in many areas. Over the years, this species has been studied intensively by ornithologists and they have made a collaborative effort to document its habitat and other features. The Cooper's hawk is medium sized and has rounded wings with a long rounded tail. Males measure approximately 39 cm and females approximately 45 cm. Younger birds have yellow legs and adult birds have orange or red colored legs. Males are brighter colored than females. Adult birds have a dark gray-blue crown that contrasts with their lighter-colored nape. The tails have four alternating straight bands, dark brown and light brown in adults. The tip of the tail may sometimes appear white. Some of the areas where the Cooper population...... middle of paper ...... itchy voice change with the age of the bird. The best known and identified cry is the cak-cak-cak or “alarm cry”. The kik is the most common call of the male, signaling his presence in the area. Female whaaa and young birds chirp. The Cooper's Hawk occasionally runs or walks on the ground, most of the time it rests on trees or flies. The bird sleeps upright on one leg, with its head folded between its back feathers. The bird maintains its health and feathers by preening, stretching, bathing in water, and scratching its head with its toes. They lay eggs after breeding, take good care of them and protect their chicks. Overall, the birds adapt to the human lifestyle and the population begins to slowly increase. They are very interesting birds and retain high adaptive characteristics to survive in today's changing global conditions..