Pigeons perch on a post outside of Central Park in New York in 2020.
  • Urban birds are singing more since the pandemic began to spread across the world, researchers wrote.
  • The study links less noise pollution and fewer crowds to birds chirping earlier in the morning.
  • Researchers say this finding speaks to the adaptability of urban wildlife.
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If you live in a city, you may have noticed that birds are chirping more frequently.

The reason why can be traced back to about a year ago when cities across the world began to shut down in response to the coronavirus pandemic, according to a group of Spanish scientists who have been studying bird behaviours since.

According to their research published in Proceedings of the Royal Society B, urban birds were used to the hustle and bustle of cities before the pandemic. Loud noises and packed streets were just a part of their daily lives.

But when the pandemic forced people inside, it was suddenly quiet and empty outside.

"The Covid-19 lockdown provided us with an exceptional experiment," one researcher, Oscar Gordo from the Catalan Ornithological Institute in Barcelona, told Salon. "We removed most of the noise and disturbances to which birds are subjected to."

Bird calls travel easiest through the atmosphere at dawn, and without noise pollution, birds modified their behaviour to sing earlier in the morning, just like they would if they had been born into natural conditions.

"We were surprised to find a so sudden change in the daily routines of birds," Gordo told Salon. "They just needed a few weeks to show a pattern of daily activity as the one observed in wild populations."

While the birds changed their behaviours surprisingly fast, the world wasn't in lockdown for long enough for birds populations in cities to increase substantially, according to the study.

The authors conducted their research in northeastern Spanish cities. The study highlights the adaptability of city birds.

"Our study demonstrated that birds are able to adapt really fast their behaviour to make an optimal use of their environment," Gordo told Salon. "Therefore urban birds and maybe other urban animals have indeed a surprising behavioural plasticity."

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