Can Hummingbirds Snore?

The bird in this viral video is more likely stressed than it is dreaming.

With more than 2.7 million views, you may already know about the snoring hummingbird video, footage that resulted from a scientific study measuring hummingbird oxygen consumption. 

Now, for the debunking: This Amethyst-throated Sunangel is not exactly sleeping and it’s certainly not snoring. “Hummingbirds don’t snore,” says Alejandro Rico-Guevara, a hummingbird researcher from the University of Connecticut. “This is not natural for a resting behavior.”

Something about the bird is indeed off. The open mouth and exposed tongue are strange, says Rico-Guevara, who scientifically described how hummingbirds drink nectar in 2011. “They don’t like their tongues drying out.”

The video’s publisher, who was studying for a masters degree in ornithology upon publishing the video three years ago, suggests that the hummingbird’s mouth is open because it is taking in extra oxygen to come out of torpor—a short, nightly hibernation in which birds lower their breathing rate and body temperature to conserve energy on cool evenings.

But Rico-Guevara has seen hummingbirds in torpor, and he says that while they may shiver to get warm, “they never make noises like this.”

What we’re hearing, he thinks, is more likely a sound of stress. Rico-Guevara captures Amethyst-throated Sunangels in mist nests for his research, and recalls juveniles sometimes emitting distress noises oddly similar to this “snore.”

“To me, this is a juvenile calling for help,” says Rico-Guevara. (He knows it’s a young bird thanks to the yellow coloring on the corner of the mouth, which serves as a target for parents to feed their fledglings.) From a purely logical viewpoint, he adds, it makes no sense for a bird to sleepily snore in a predator-packed forest all night—“Snoring is not adaptive!” In people, snoring leads to more broken sleep than it does to anything beneficial.

The good news is that even if the bird wasn't snoring, this little one made out all right. “After the experiment was done, I watched the bird fly away myself, it was fine,” the video’s author writes. “The welfare of birds means the world to me, and I am dedicating my career to their conservation.”