Mysterious deaths of birds in Mexico leaves netizens puzzled

Chihuahua: A viral video depicting the deaths of hundreds of blackbirds swarming as a flock over houses in the city of Chihuahua in Mexico has given rise to multiple theories on why the birds fell dead to the sidewalks.

Security footage that has gone viral for the bizarre nature of the incident shows how hundreds of yellow-headed blackbirds appeared to fall dead on February 7. According to local news outlet El Heraldo de Chihuahua, which first reported the story, residents of Chihuahua in Mexico called the police after discovering the dead birds on the sidewalk.

The birds can be seen descending in their flock to houses and then inexplicably falling dead. Sectional police of Alvaro Obregon reported that they began to receive calls about the dead birds at around 8.20 am on Monday.

As the video went viral around the globe, people began to speculate on the strange phenomenon, with some theorising that heavy pollution or toxic fumes could be responsible for the deaths of the birds, while others suggested electrocution. Another popular conspiracy theory is the role of 5G networks which have falsely been implicated in bird deaths in Europe before.

But Dr Richard Broughton, an ecologist with the UK Centre for Ecology & Hydrology, told The Guardian that blame for the incident could lie with a predatory bird.

"This looks like a raptor like a peregrine or hawk has been chasing a flock, like they do with murmurating starlings, and they have crashed as the flock was forced low," he said. "You can see that they act like a wave at the beginning, as if they are being flushed from above."

The yellow and black fowl had been wintering in Mexico after arriving in the country from Canada. Adults of the species are preyed upon by the Northern Harrier - a predator common in Mexico during the colder winter months. Much like starlings, these birds are often seen travelling in large flocks, making incidents such as these more likely during their annual migration.

The footage of the bird deaths has been viewed more than 1.4 million times on Twitter and shared widely on Facebook.