My bird feeders are busy today with the new layer of snow and real winter cold. The birds act nervous, though, and make mad dashes for the cover of nearby blue spruce trees and a brush pile every minute or two. They have good reason to be nervous. A young Cooper’s hawk is making the rounds of area bird feeders, and it’s not looking for sunflower seed. It’s possible that the hawk was raised in a nest only a few hundred feet west of our house, but it could also be a migrant spending the winter here.
Crow-sized Cooper’s hawks are fairly common nesters in central Iowa woodlands again, after being quite rare for more than 50 years. They are the middle-sized member of a group of hawks called accipiters, or "bird hawks." They are so called because birds are their favored prey. Unlike the larger soaring hawks like our local red tails, accipiters tend to hunt by perching quietly in ambush, and then overtaking their prey with an explosive burst of speed. They are aggressive hunters that will often pursue their prey right into thickets and brush piles. I saw the young "Coop" emerge from my brush pile with an English sparrow just last week.
My yard birds could also be nervous because there are still a few migrating sharp-shinned hawks in the area, too. Blue jay-sized "sharpies" look almost identical to their larger cousins, the Cooper’s hawks. Young are brown above and buff below. Adults have dark, slate gray backs and buff breasts. Sharpies hunt in much the same way as Cooper’s hawks, but must keep a sharp lookout for their larger cousins, who would quite willingly make a meal of them, too.
Feeder watchers seldom see the largest and much rarer member of the accipiter clan, the northern goshawk. These powerful hunters rarely come this far south, even in winter, and when they do, they prefer larger prey like grouse or rabbits. The young of this species are also streaked with brown, but the adults are gray on the back and silver-gray on the breast.
All accipiters are built for rapid bursts of flight dodging through trees. Their wings are relatively short for hawks and are wide and rounded. They have long tails to aid in maneuvering through their forest homes. They are capable of soaring, but tend to do so only during migration. Like many raptors, they cover large areas as they hunt for food. They may hunt near your feeder for a few hours and not be back for days.
People who feed birds near more open country may be visited by the small and most brightly colored member of the falcon clan, the kestrel, also known as the sparrow hawk. Kestrels often perch on power lines while looking for foods that include small birds and mice, but will also hunt from the wing. They’ll sometimes hover for a few moments on rapidly-beating wings to study a spot more closely. If food is spotted, they’ll fold up and drop on it in the blink of an eye. We once watched a kestrel pick a downy woodpecker off the truck of a tree. The woodpecker proved almost more than the little falcon could handle as they wrestled for several minutes, but it ultimately became a meal for the hawk.
Short days mean that some birds will be feeding before sunrise and after sunset in order to pack in enough energy to fuel them through another long, cold night. Cardinals and dark-eyed juncos are among those that expose themselves to yet another group of raptors, the owls, when their daily active periods overlap. I often found cardinal feathers in wood duck boxes being used by screech owls for roosting shelters and found junco feathers under a great horned owl nest where young were being fed.
Like all people who feed birds, I prize my few colorful cardinals, jays and finches, and hope that they don’t get picked off by a passing raptor. I’m always thrilled when I get to watch one of those winged hunters attack, though. I enjoy them all and hope I’ll be able to see quite a few of them on Saturday, Dec. 14, during the annual Audubon Society Christmas Bird Count!
(Steve Lekwa is the former director of Story County Conservation.)