Broad-winged hawks are a southbound spectacle
For those of you who have never seen one, a broad-winged hawk is best described as a small cousin of the red-tailed hawk.
Both birds are members of a group of raptors known as “Buteos” (pronounced byoo-tee-ohs), which are characterized by their large, thick-set bodies; broad wings; and rounded, fan-shaped tails. While the red-tailed hawk’s most notable field characteristic is its red-orange tail, the broad-wing’s tail is marked with thick, alternating bands of black and white.
The buteos are the soaring hawks that can spend effortless hours circling in the sky while they keep an eye out for the small animals they prey upon. Red-tailed hawks are the largest buteos in our area, with a wingspan of up to 5 feet, and are able to tackle large prey animals such as muskrats and woodchucks. They are not limited to these larger animals, however, and will basically eat anything they can kill.
A varied diet
With a wingspan of only 3 feet, broad-winged hawks are much smaller birds and must specialize a bit. As an example, it has been discovered that broad-winged hawks are quite partial to toads, which they hunt during the spring breeding season. They will also eat frogs, snakes, mice, voles, rabbits, chipmunks, squirrels and small birds. As odd as it may sound, broad-winged hawks will even eat earthworms, which they may find in fields after a heavy rain.
Because of their reliance on smaller prey animals, many of which hibernate during the winter, broad-winged hawks are migratory. They spend the winter months as far south as northern Argentina but are largely concentrated in Central America and northern South America. During our winter months, broad-winged hawks are perhaps the single most abundant hawk in the woodlands of Panama and Costa Rica.
They reappear in our area in early April and begin a courtship that remains largely unknown to us. We do know that the male will bring food to the female and present it to her with some head bobbing. She may even bob her head back before accepting the food from him. The pair may also spend time soaring in unison above their territory, but whatever is involved in their courtship it doesn’t take long. Often, the female will lay her eggs just one week after her arrival.
Before she can lay her eggs, however, the female needs a nest. These structures are large masses of sticks that can be found in any sort of deciduous tree that fits the bill. Broad-winged hawks prefer to place their nests high off the ground, but just below the canopy layer of overstory trees in convenient three- or four-branch intersections.
As a result, broad-winged hawks usually choose their nest tree based on its characteristics rather than on its species, but a large yellow birch is a classic broad-winged nesting tree here in the Northeast.
Broad-winged hawks are very quiet and gentle birds, and as a result they often go unnoticed while they are building their nests, incubating their eggs and raising their chicks.
In late August and throughout September, broad-winged hawks will gather in huge flocks. On favorable days, they will migrate en masse, in large circling formations known as “kettles.” The hawks will search for thermals, invisible columns of warm air that can lift the birds high into the air.
Once they have reached a sufficient altitude, they will fix their wings and head south in search of the next thermal. On clear days in late summer and early fall they can add a genuine element of spectacle to the natural world, there for anyone willing to look up to see.
Bill Danielson is a professional nature photographer and author living in Altamont. Contact him at www.speakingofnature.com.