Krider's hawk or Krider's red-tailed hawk is a subspecies of red-tailed hawk. In the breeding season, it occurs from southern Alberta, southern Saskatchewan, southern Manitoba, and extremewestern Ontario south to south-central Montana, Wyoming, western Nebraska, and western Minnesota. In winter, it occurs from South Dakota and southern Minnesota south to Arizona, New Mexico, Texas and Louisiana. This is about the same size as the western red-tailed hawk. Wing chord averages in males and. Males and females average in tail length, in tarsal length and in culmen length. More authorities than not consider this a color morph of the western red-tail than a subspecies in recent classification, but others consider it a valid race. Hybridization is possible and known to occur, most extensively with B. j. calurus, but also in the Dakotas and eastern Wyoming with the eastern red-tailed hawk and in Alberta some possible Krider's hybrids with Harlan's hawks have been reported. Krider's hawk is paler than other red tails, with the head typically white with somewhat darker nape, variable dark markings about the face. The upperparts are light brown and upper-wing coverts are heavily mottled white, the tail is typically whitish at the base otherwise a fairly pale pinkrufous. Krider's hawks are distinctly all white underneath with no trace of a belly band, unlike the palest B. m. harlani. There is much individual variation, which is complicated by possible racial hybridization. One study found males more likely than females to have pure B. j. krideriicharacteristics. The same study found that Krider's hawks were fully specialized as breeders for the prairie habitat, favoring much more open areas than do other red tails or especially Harlan's hawks. While wintering Harlan's and Krider's hawks frequently occur in the same general areas, but their habitat preferences there were highly different, Harlan's favoring thickly timbered areas and Krider's in quite grassy open areas. Wintering Krider's also used different and more open habitats than resident red tails. These authors questioned whether Krider's hawk was once a pure subspecies, similar to the prairie merlin, but following human habitat alterations, B. j. calurus and B. j. borealis encroached into their breeding ranges and diluted their characteristics.
