SWAINSONS HAWKS: Long Distance Migrators

by Dave Hanks

From Idaho to Argentina is quite a flight, even for an airplane, but that is where this hawk goes each winter. Swainson’s Hawks love rabbits and ground squirrels and open country is where the hunting is best. They trade their niche here, each winter, with the Rough-legged Hawk –who comes down from the far north each late autumn.

Look for the tan bib and for some white around the chin, and don’t confuse it with the Red-tailed Hawk, who has a belly band. This raptor is tamer and easier to get close to than others. When driving in open country, they can often be seen perched on roadside posts. We like to visit the Centennial Valley of Montana every September. The new crop of hawks have fledged by then and many kinds are scattered across the upper Red Rock Lakes area. Swainson’s are well represented among the offerings.

This is a western hawk and arrives here in April and leaves in September. It may hunt from a tall perch but usually soars to spot prey. It will also take snakes, frogs, birds, and small rodents. Young hawks eat a lot of grasshoppers and crickets while learning to care for themselves. Nature has an ingenious adaptation for predatory birds. The fledglings are half again heavier than the adults when they leave the nest. This extra weight is lost as they learn to hunt.

Swainson’s Hawks are monogamous and return to the same nest every year. The nest will usually be in a tree next to farmland or next to a riparian (streamside) area. Four white eggs are laid and they require 34 to 35 days to incubate. The babies will fledge one month later. In two years the immature hawks will be ready to breed.

When in open country, keep your eyes alert and listen for a drawn out “skreeee”. Perhaps you might see this bird.

(Surveying the landscape from a north Heglar Canyon road post)