"But Sue Anne Zollinger, an ornithologist from Manchester Metropolitan University, cautions: Don't believe everything you hear. With the decrease in traffic, there's less noise pollution. That means birds have less noise to compete with, she says. 'Although our perception might be that they're singing louder, it's actually likely in places that are typically noisy that they're singing more quietly than normal... But when the noise is gone, they're probably singing quieter than they do normally.'"
NPR reports.
