Oklahoma Breeding Bird Species Profile: Swainson's Hawk

A lanky hawk of the west, desert, prairie, and farmland, the Swainson's Hawk is one of four buteos with four notched primaries (as opposed to five).  They are uncommon and hunt from the air, a perch (still-hunting) or even upon the ground, running after their quarry.  They generally feed on reptiles or small mammals in summer, then resort to grasshoppers, locusts, and other invertebrates for the remainder of the year.

Known as the locust or grasshopper hawk, this handsome bird was named after William Swainson, a British naturalist.  Swainson felt like many of us do when it comes to living things.  They were an inherent passion.

Suspected to have a migration range of 14,000 miles, this raptor is likely the longest traveler in the family of hawks.  Wintering in Argentina or Southern Brazil, immature Swainson's Hawks can see their way to southern Canada by late March and their migration can peak from mid-April forward.

Having diverse and somewhat unusual eating habits, this hawk will take Mallards, fledged Lark Buntings, incapacitated Sage Grouse, toads, salamanders, whip snakes, the American Kestrel, young Short-eared Owls, and several others.  They are also known for hunting upon freshly plowed fields for rodents, and are opportunistic feeders, as well.

These birds come in a light, intermediate and dark morph.  Oklahoma has the lowest percentage of dark morphs, while California has the highest.  They can behave similarly to the Northern Harrier by flying low to the ground at times.  Wingbeats are deep and loose, and they will soar with wings in a dihedral angle, or an angle between two intersecting planes.  They glide like an Osprey would.  These are all tell tale signs of how to spot the bird on a hawk watch.

Last year, while visiting the Oklahoma Panhandle, these were relatively common, perching on telephone poles and fence posts.  This photo came from that area, with the sun behind the bird.

                                                                Swainson's Hawk
                                                            Cimmaron County, OK

Another interesting point, also from last year, was during monarch migration.  A notation was made on a butterfly site to go outside and look up, which I did.  I saw no monarchs, but observed fifteen Swainson's Hawks heading southbound.  It was one of the most remarkable sights ever seen, especially with the way that the light struck the underwings and their breasts in late afternoon, as they simply glowed.

Swainson's will hybridize with Red-tailed and Rough-legged Hawks, but it is questionable if Ferruginous Hawks are in the mix.