A rash of dead and dying pigeons -- dubbed "zombie pigeons" because of their bizarre behavior -- worries Moscow residents unsure of what's causing the unsettling phenomenon.
Muscovites began to pay attention to the feathery "zombies" last week, according to The Wall Street Journal, when residents started witnessing pigeons walking backward in circles or standing with their heads resting on the ground.
"When I walk to work, I usually see pigeons running and jumping around," a Moscow resident identified as Umid told Radio Free Europe. "But recently, they haven't been reacting to anything at all. When a person walks past them, they used to fly away. But now they just sit there in a kind of funk and don't even pay attention to you. They're just not normal. I've seen some pigeons behaving very strangely, turning around in circles."
Even more concerning, Russia's Federal Veterinary and Phytosanitary Inspection Service initially said the birds had been infected with Newcastle disease virus, a contagious and fatal virus that can spread to humans, according to The Moscow Times. However, it now appears that many of the birds are suffering from salmonella poisoning, which is not dangerous to humans, reports the Times.
Autopsied pigeons confirmed signs of the more common salmonella infection, said Leonid Pechatnikov, Moscow's deputy mayor for social issues, according to RT.
Russia's chief health inspector, Gennady Onishchenko, called pigeons some "of the dirtiest, stupidest birds there are" and said residents had no reason to worry, although he cautioned against personally handling any sick birds, according to Radio Free Europe.
The Guardian noted that some Russians have connected the bird deaths to an end-of-times prediction from Russian mystic-to-the-czars, Grigory Rasputin.
In fact, stories of birds falling from the sky or dying en masse are reported around the world with regularity -- and never fail to attract dire apocalyptic predictions.
The United Nations Environment Program in 2011 called for more research into such deaths. Mass bird deaths happen all the time, however, contends Petter Boeckman, a zoologist at the Norwegian Natural History Museum. The response often has more to do with cultural lore than with science.
"In the United States the reaction is 'oh no, Doomsday is coming,'" Boeckman told Reuters. "In Sweden, they say 'let's call the veterinary authorities.'"
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