In the Mexican city of Cuauhtémoc last week, a security camera captured footage of a flock of yellow-headed blackbirds falling from the sky. Some then flew off but many didn't survive. No, it wasn't 5G radio waves jamming their navigation systems. From The Guardian:
"For my part and from one video and no toxicology, I'd still say the most probable cause is the flock murmurating to avoid a predatory raptor and hitting the ground," [Manchester Metropolitan University conservation biologist Alexander Lees] said.
"There always seems to be a kneejerk response to blame environmental pollutants, but collisions with infrastructure are very common. In a tightly packed flock, the birds are following the movements of the bird in front rather than actually interpreting their wider surroundings, so it isn't unexpected that such events happen occasionally."