An Urban Wildlife Mystery
not have talons. They belong instead to the nightjar family and are related to whip-poor-wills and chuck-will's widows.
Common nighthawks have an unusual perch because they pitch forward on their breasts. That is why they sit long-ways on a power line. If they sat cross-ways, they would fall forward. Their legs are small and positioned somewhat awkwardly toward their tail ends. Consequently, they can't walk on the ground very well. Flying, as we witnessed from the tennis court, is their forté.
They migrate from South America and make their appearance in Missouri in late April and depart by late September. On the court, we saw them chasing down moths. To accomplish this, they are equipped with wide gaping, bristle-fringed bills that act as aerial sweepers, scooping insects on the fly. These facial bristles are specialized feathers and are only concentrated around their mouths. One book I read suggested they may function a little like cat whiskers, amplifying the sensation of touch. They may also serve as a sort of funnel, ushering more insects into the bird's open mouth.
The book also described their daredevil, downward plunges through the evening sky. It dawned on me those were nighthawks we had seen swooping over the physics building the previous spring. Only males make these plunges, and it's an effort to attract females for mating. As he comes searing down and abruptly levels off, his mouth and plumage catch the wind and make a thudding, windy noise. Females sometimes squeak when they fly, and males squeak repeatedly on the ascent. Once two birds have paired off, the male chases away any other courting males nearby and continues to perform celebratory loops, dives and swerves.
Nighthawk pairs don't build nests. Rather, they search for out-of-the-way rock surfaces, crevices in cliffs or a favorite urban nesting spot: gravel rooftops. Many buildings on the M.U. campus-including Ellis Library-have gravel roofs. Females lay two longish, somewhat elliptical eggs and arrange them pointy ends inward, which helps the adults cover them efficiently during incubation. They also cover the eggs with dusty-brown, downy feathers, which helps keep them camouflaged. Both males and females sit on the eggs and help feed the young after they hatch. Little ones learn to fly in about 21 days and linger near the nest. They raise their own young the next year.
Nighthawks belie their name. They often are around during the day, both perched and on the wing. At dusk they set out to catch insects-the only things they eat-but generally settle down after the sky goes black, making way for whip-poor-wills and owls.
And suddenly, Christopher's story came back to me. Could one of these birds have been the night time perpetrator that thwacked him in the head that cool spring evening?
Brad Jacobs, an ornithologist with the Conservation Department, listened politely as I recounted Chris' night time escapade with the spare hair and fencing mask. "It could have been a screech owl, maybe, going for the pony tail, but that's a long shot. An Eastern Kingbird might have done it, or a mockingbird. Mockingbirds and kingbirds will defend their territory. Was he near any bushes that may have held a nest?"
I said no, then ventured that perhaps he had been thwacked by a common nighthawk.
"It's possible," Jacobs said. "It could have been a common night-hawk, especially that time of year. They're back in Columbia by then." That was all I needed to hear.