Hobbits Mommie
Songster
Have you seen this in person? Odds are witness was doing a lot of blinking and not paying attention to the world around. I have seen people, several at a time, walk down a sidewalk right past a Coopers Hawk that was walking on ground picking up sticks for nest. The people did not even notice the sizable bird with pretty gray coloration and fierce red eyes very close to their feet. I think that pattern represents the majority of people, even those keeping chickens. Lost connections to the world.
I actually had one swoop down to try to get my Chihuahua. When they fly their wings are silent so unless you catch one at rest, you won't have any warning. I also had one swoop onto my covered porch and grab a pigeon that was foraging no more than 2 feet from me.