Pop Quiz! White-Winged Crossbills, Accipiter Hawks & Northern Hawk Owl

A crookedness of White-winged crossbills, males and females, Phippsburg, Maine

Sharp-shinned and Cooper's hawks, both accipiters, clock-wise from bottom left: Cooper's, Sharp-shinned (perched), Cooper's (perched), Cooper's (flight), bottom right - Sharp-shinned (take-off)

"You got a problem with this?"

Northern-hawk owl, perched, flight and eating White-winged crossbills in  Bristol, Maine

White-winged crossbill feathers, probably female, aftermath of Sharp-shinned hawk attack. Note that at the mid right of the image above the blood mark is a crossbill bill.

     I love pop quizzes, but most of the people I know hate them. I think that's because people don't like being put on the spot. They like lots of advance time to study and prepare answers so they don't look stupid. Me? I'm quite willing to look stupid without any advance notice required. The images above are of Sharp-shinned and Cooper's hawks, a Northern Hawk owl and White-winged crossbills, pre and post mortem. Do you know what they all have in common? And don't say "Ya, the one on the bottom is dead." That would be just stupid. The hawks and the hawk owl are three species of predatory birds that eat other birds. They all eat White-winged crossbills when they can find them. The Northern hawk owl isn't a hawk at all, though it does behave like a hawk. And, the owl and the White-winged crossbills have more in common than the hawks or the owl. Don't you wish you had studied for this exam?

     White-winged crossbills and the Northern Hawk owl are boreal irruptives in the southern part of Maine.  Neither bird is migratory, but they both occasionally fly south of their usual range when competition for food is too high. In 2007, a White-winged crossbill was found dead in a parking lot in Florida. No one knows for sure how it got there, but it's safe to say it didn't fly. One theory is that it had been hit by a recreational vehicle then rode to Florida stuck in the vehicle's grill. It just fell off in the parking lot on arrival.

     Food supply of the White-winged crossbills and Northern Hawk owls can drop if there is a 'crop' failure or reduction in prey population. Crossbills eat seeds. Their bills are highly adapted for prying seeds from the cones of conifers of the northern forests. The bill holds the cone or seed hull open while the tongue plucks the meat out. I once knew a heavy smoker who could flip a lit cigarette butt around with his tongue so that the lit end was inside his mouth. He would close his lips and blow the smoke out of his nose. Because I knew the guy personally, I thought it was a cool trick. Remember the legendary woman who could tie a Maraschino cherry stem into a knot with her tongue. There's always some guy who says he knew her in high school. White-winged Crossbills with lower mandibles crossing to the right are three times more common than those with lower mandibles crossing to the left, like people that are left handed.

     The birds in these photos were enjoying black oil sunflower seeds in my feeders ans spillage on the ground. Individual White-winged Crossbills can eat up to 3,000 conifer seeds each day. Crossbills breed opportunistically throughout the year whenever food is sufficient for the female to form eggs and raise young. The species has been recorded breeding in all 12 months. A group of crossbills are collectively known as a "wrap" or a "crookedness" of crossbills.

     Northern Hawk owls, also called simply "Hawk owls," are unique among owls. They have long tails and pointed wings and their flight is like accipiter hawks. In addition, they tend to bob their tails when perched and are adept at hovering like kestrels. Their long tail distinguishes them from all other owls. This owl is about the size of a crow.

    Hawk owls eat rodents, mostly voles and in the winter, other birds. They will occasionally take a frog or even fish! Diurnal hunters, Hawk owls like the hawks they are named for, sit on perches and swoop to the ground for prey. They hunt mostly by sight and can see prey up to half a mile distant. Like a true owl, they also can hear rodents under as much as a foot of snow.
     The Hawk owl in the images above was dining on a female White-winged crossbill.  Both of these species were irruptives in Maine in the winter of 2009. This year, there are plenty of White-winged crossbills here, but so far, no one has reported a Hawk owl this winter. Maybe if they knew the crossbill delicacies were here they'd come around. In 2009, it was reported that several times, people who saw the owl took fat, Petco rats for the Hawk owl's pleasure. The owl swooped from its tree perch and snatched up the bewildered, rotund rats before you could say "White-winged crossbill!" Though the owl clearly found the domestic rats tasty, it was regarded as an outrage in the birding community to feed the starving bird that was far, far from home. Perhaps the crossbill that wound up in Florida perished in pursuit of an Early Bird Special after it wasn't allowed into a restaurant.

     Sharp-shinned and Cooper's hawks are accipiter hawks built for speed, because like the Hawk owl, they hunt other birds in flight. Nailing a rodent to the ground requires speed and power, but not flight maneuverability. Both species of accipiter hawks are winter regulars in Maine. When there is thick snow cover, they stalk feeder birds, as easy pickings as a senior citizen's buffet or a Petco rat. Pass the tartar sauce and the Pepcid, please.

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