Gigantic avian predators create quite a flap when they appear out of the blue.

Nobody likes it when company drops in unannounced. Especially when it drops in out of the sky. And especially when the company in question isn’t a distant relative or a next-door neighbor seeking to borrow your circular saw, but an enormous black bird with a wingspan as big as an airplane’s and a taste for human flesh.

That’s just what Lawndale, Illinois, resident Ruth Lowe had to contend with on the muggy evening of July 25, 1977. She was cleaning out the family camper in the front yard when she heard her ten-year-old son, Marlan, screaming in the backyard. Lowe, according to her own account, dashed around the house just in time to witness pretty much the last thing someone in her position would expect to witness. A gigantic black bird with an eight-foot (2.4 m) wingspan had grasped her seventy-pound (32 kg) son by the shoulders and was attempting to fly off with him.

According to Lowe, the bird came very close to succeeding. It had managed to lift the violently struggling boy off the ground and was slowly flapping its way across the yard. But apparently the load—and, perhaps, the number of screaming spectators it quickly attracted—was too much to bear. The bird dropped Marlan and soared skyward, where it flew away with a feathered companion that was every bit as large. Lowe, now joined by her husband, Jake, and their next-door neighbors James and Betty Daniels, watched the bizarre attackers depart. “If I had just had a can of beer earlier, then I could have said I imagined it,” James Daniels told United Press International. “But I didn’t have any beer that day.”

Maybe not, but officials were quick to discredit the family’s version of events. Experts pointed out, rightly, that gigantic, child-snatching black birds weren’t exactly a common sight in the skies over Illinois, or anywhere else in the western hemisphere, for that matter. Perhaps, it was suggested, they might have been turkey vultures or king vultures. But those birds, though weighing around fifty pounds (23 kg), simply aren’t big and powerful enough to contemplate picking up a struggling boy. And since vultures prefer to dine on carrion, why would they bother with live prey?

The consensus, at least among some people, was that the Lowes perhaps embellished the details of the encounter. And yet, to this day, Marlan sticks by the same version of events he and his family put forth back in 1977. They can perhaps take comfort in the fact that they’re not the only people in the area who claimed to have seen the winged behemoths. On the evening of July 28, a woman who was out driving not far from Lawndale reported being buzzed by a giant bird. And a couple of hours later on that same evening, a group of people flying model airplanes was approached by a bird with an estimated ten-foot (3 m) wingspan. The next day, mail carrier James Majors reported seeing two large birds loitering over a pig farm. Suddenly one dropped out of the sky, attacked a roughly fifty-pound (23 kg) piglet, and hauled it into the air. Shortly thereafter it landed with its prize and was joined by its companion. Together they dined on the catch.

If one can believe eyewitness accounts, suburban Illinois isn’t the only place to see giant airborne predators. A monster with a reported fifteen- to twenty-foot (4.5–6 m) wingspan flew over Middletown, Ohio, in 1967. And in the 1970s, there was a spate of Texas sightings, including a January 1976 encounter in which two San Benito police officers, Arturo Padillo and Homero Galvan, reportedly saw an enormous bird gliding over a canal. Pennsylvania seems to be a hotbed for freakish flyers, with eyewitness accounts dating back to the 1800s.

Perhaps these were examples of an animal that Native Americans called the Thunderbird—a gigantic, supposedly mythical creature said to cause thunder and lightning. These days, however, it seems to cause only consternation. Though sightings continue, there’s never been one made by any of the country’s tens of thousands of birdwatchers. That’s a bit telling, because people who can differentiate between two closely related types of finch at one hundred paces should have no trouble spotting an avian predator the size of an airliner. Also, what exactly would such giant birds eat? Maybe the cattle mutilation people should get together with the Thunderbird enthusiasts and compare notes.