|Buteo||swainsoni||NA, MA||nw, wc|
Members of the genus Buteo are broad-winged, broad-tailed hawks, Well adapted for soaring. The bill, legs and talons are of average proportions. There is much colour variation both within the species, and, by way of phases, within individual species. In all cases the young are quite different from adults in that they are all well camouflaged with an overall brown appearance with varying amounts of striping below and paler mottling above.
The 25 species are spread worldwide with the exception of Australasia and much of the Indian sub-continent.
dark flightfeathers. Tail is gray above, often becoming white at the base. There are confusing individuals with light breasts, and dark melanistic birds; note the underwing with its dark flight feathers. The Swainson’s Hawk is not, to many, the most impressive member of the Buteo genus. It tends to be (compared with, for example, the Red-tailed Hawk) rather lank and long-winged; a little sluggish in its habits and, although well able to soar with the rest of the genus, more likely to be found perched on a post, or even on the ground.
Listen to the sound of Swainsons Hawk
Copyright remark: Most sounds derived from xeno-canto
|wingspan min.:||124||cm||wingspan max.:||137||cm|
|size min.:||48||cm||size max.:||56||cm|
|incubation min.:||34||days||incubation max.:||35||days|
|fledging min.:||42||days||fledging max.:||44||days|
Breeds most commonly on northern Great Plains, in prairie regions with scattered groves of trees for nest sites. Less common in dry grassland farther west and in heavily farmed country. In migration, often pauses in fields where insect lar
vae may have been turned up by the plow.
Nest: Site is usually in tree or large shrub in open country, usually 15-30′ above ground, but may be lower or higher; generally well hidden within foliage. Sometimes nests on ledge of cliff or steep slope. Nest is a platform of sticks, lined with finer twigs, weeds. Often adds leafy green branches to nest. Clutch 2-3, sometimes 1 or 4. Pale bluish white fading to dull white, usually lightly spotted with brown. Incubation almost entirely by female, about 34-35 days. Male brings food to female during incubation.
Young: Both parents bring food for young, but at first, female may remain with young much of time while male hunts. Young can fly about 42-44 days after hatching; may remain with parents until fall migration.
Video Swainsons Hawk
copyright: Matt Giovanni
It is estimated that about 20,000 Swainson’s Hawks died during the winter of 1995-1996 through the use of a pesticide called monocrotophos in their Argentinean wintering grounds. The pesticide was used to control the grasshoppers and caterpillars which are the main food for the hawks (and numerous other species) when they are there. The good news is that there followed an international effort to solve the problem, involving Argentina, USA, Canada and Switzerland. The end result was that the chemical companies removed the monocrotophos from the area where the fatalities occurred. Argentina banned the use of monocrotophos nationally in March 2000