Photo by Bob Gress
Length: 17 - 22 inches
Wingspread: 47 - 54 inches
Weight: 1.3 - 2.7 pounds
These gregarious hawks can often be found feeding and migrating in flocks that may
total more than a thousand birds. There are no recognized subspecies of Swainsons
hawks, but they can be light, rufous or dark morph birds. On lighter colored birds a dark
brown bib can be seen between a lighter colored chin and belly. When seen in flight the
leading edge of the wing is light, and the flight feathers are dark. Juveniles have a
Swainsons hawks breed from southwestern Canada through central and western
United States to the northern parts of Mexico. A large majority of the birds winter in the
pampas of Argentina. For the birds that breed in Canada and winter in Argentina that means
traveling over 6,000 miles, a trip that may take nearly 2 months to complete. Populations
have been reduced since the early 1900s due to loss of habitat and declining prey
populations as a direct result of pesticide application to insects in agricultural crops.
Non-breeding birds eat mostly large insects. Grasshoppers seem to be a favorite.
They are often seen foraging in fields where farm machinery disturbs their prey. During
the breeding season Swainsons hawks eat a more typical hawk diet of rodents,
rabbits, ground squirrels, birds and reptiles.
Other Kansas Hawks
Text: Bob Gress and Vanessa Avara
Web Design: Jim Mason