The mystery of the viral video showing the sudden death of around 100 yellow-headed blackbirds in Mexico has now been solved.
The mass death took place in the residential suburb of Alvaro Obregon in the city of Cuauhtemoc in the Mexican state of Chihuahua on the morning of 7th February.
Footage shows how hundreds of yellow-headed blackbirds (Xanthocephalus xanthocephalus) suddenly plummet from the sky in a huge mass.
Most of the birds, which were wintering in Mexico at the time, are seen taking flight again, while around 100 remain motionless on the street.
Another video shows someone sweeping scores of the lifeless birds from the pavement onto the tarmac road.
The cause of the eerie event stumped experts, with some suggesting they might have inhaled toxic fumes and become disorientated.
Others suggested they might have carried out a risky manoeuvre to avoid a predator in pursuit, such as a falcon, which went wrong.
But now, the Federal Environmental Protection Agency (PROFEPA) says it has cracked the case.
The agency published a statement saying: “After carrying out an inspection to corroborate the facts reported in the locality, PROFEPA has confirmed that the death of the approximately 100 yellow-headed blackbirds (Xanthocephalus xanthocephalus) was due to the flock’s collision against power lines.
“By making direct contact with the cables, the birds received an electrical voltage that caused their death. The rest received a minor shock that stunned them, but allowed them to continue their flight.”
Despite the birds’ mass deaths, the species remains classified as one of ‘least concern’ by the International Union for Conservation of Nature.