Hawks

Hawks

Species In This Category

About Hawks

Hawk is a common name for some small to medium-sized diurnal birds of prey, widely distributed and varying greatly in size. The subfamily Accipitrinae includes goshawks, sparrowhawks, the sharp-shinned hawk and others. These are mainly woodland birds with long tails and high visual acuity, hunting by sudden dashes from a concealed perch. (1) In the Americas, members of the Buteo group are also called hawks; these are called buzzards in other parts of the world. Generally buteos have broad wings and sturdy builds. They are relatively larger winged, shorter-tailed and soar more extensively in open areas than accipiters, descending or pouncing on their prey rather than making fast horizontal pursuit.

  1. Source: Campbell, B., Lack.E (2013) A Dictionary of Birds. p.273

Hawk Facts

  1. Hawks have four types of colour receptors in the eye. These give birds the ability to perceive not only the visible range but also the ultraviolet part of the spectrum, and other adaptations allow for the detection of polarised light or magnetic fields. This is due to the many photoreceptors in the retina (up to 1,000,000 per square mm for Buteo, against 200,000 for humans), an exceptional number of nerves connecting these receptors to the brain, and an indented fovea, which magnifies the central portion of the visual field.(1) (2)
  2. Like most birds, the hawk migrates in the autumn and the spring. Different types of hawks choose separate times in both of the seasons to migrate north or south. The entire autumn migrating season extends all the way from August to half way through December.(3)
  3. The idea of flocking during migration has been closely analysed, and there is a conclusion that it is a commutative tool used by birds and other animals to increase survival. It has become very clear to observers that a bird traveling in a flock has a greater chance of survival than if it made the journey alone. Another word used in the United States that has the same meaning as "flock," particularly in terms of groups of hawks, is "kettle."(4)
  4. The method that hawks use to reproduce is different from most. The male and female will fly together up in the air in a circular motion. Once the two get to a certain height, the male will dive toward the female and then they will raise back to the height again. The two birds will repeat this until finally the male latches onto the female and they begin to free-fall down to earth.(5)
  5. The greatest factor endangering hawks is loss of habitat. Deforestation and urbanization not only reduce food supplies but also available nesting locations. Endangered or threatened species in the US include the the Hawaiian Hawk, the Puerto Rican Broad-winged Hawk, and the Puerto Rican Sharp-shinned Hawk.the Common Nighthawk is considered in steep decline. (6)
  6. Hawks' acute keen eyesight, muscular legs; powerful, sharp claws and sharply hooked bills are perfect adaptations for hunting, capturing their prey and tearing flesh to a manageable size for eating.(7)

Hawk Sources

  1. Source: "Hawks". beautyofbirds.com. Retrieved 2010-01-30.
  2. Source: Kirschbaum, Kari. "Family Accipitridae". AnimalDiversity Web. University of Michigan Museum of Zoology. Retrieved 2010-01-30.
  3. Source: Heintzelman, Donald S. (1986). The Migration of Hawks. Bloomington: Indiana University Press. p. 40.
  4. Source: Kerlinger, Paul (1989). Flight Strategies of Migrating Hawks. Chicago: The University of Chicago Press. pp. 57–58,153.
  5. Source: Red-Tailed Hawk". National Geographic. Retrieved 18 October 2012.
  6. Source: Common Birds in Steep Decline and Watch List, The State of the Birds 2014, United States of America, Accessed January 8, 2016. Details here
  7. Source: Hawks: Interesting Facts and Species Information, AvianWeb, Beauty of Birds, Accessed January 9, 2016. Details here