Key Points:
- Human-generated noise disrupts bird communication, foraging, and predator awareness worldwide.
- Noise pollution negatively affects reproduction, with ground-nesting birds and urban populations most impacted.
- Practical solutions exist, such as designing structures to reduce sound, but awareness and action are needed.
PARIS: Human-generated noise is interfering with bird behaviour across the globe, disrupting everything from courtship songs to feeding and predator avoidance, according to a large-scale study published on Wednesday.
The research, led by Natalie Madden at the University of Michigan, reviewed almost four decades of scientific literature and found that noises produced by humans — from traffic and construction to airplanes — were affecting birds on six continents, with “strong negative effects” on their reproductive success.
While previous studies examined the impact of individual noise sources on single species, this study performed a broader meta-analysis, pooling data published since 1990 across 160 bird species to detect global trends.
According to AFP, the findings, published in Proceedings of the Royal Society B, provide clear evidence of a pervasive effect of noise pollution on avian populations worldwide.
“We found that noise significantly impacts communication, risk behaviours, foraging, aggression, and physiology, and had a strong effect on habitat use and a negative impact on reproduction,” the study said.
Birds rely heavily on acoustic information to survive, making them particularly vulnerable to modern sounds produced by urban life and human activity.
“They use song to find mates, calls to warn of predators, and chicks make begging calls to alert parents when they’re hungry,” Madden explained. “So if there’s loud noise in the environment, can they still hear signals from their own species?”
In some cases, noise pollution disrupted mating displays, forced males to alter their courtship songs, or masked communication between chicks and parents.
Underappreciated consequences
The study found that responses varied by species. Birds nesting close to the ground experienced greater reproductive harm, while those in open nests suffered stronger impacts on growth.
Urban-dwelling birds also exhibited higher stress hormone levels compared to rural counterparts.
Researchers noted that noise pollution is an underappreciated threat to wildlife, often overlooked compared to the more widely discussed drivers of biodiversity loss and climate change.
According to the International Union for Conservation of Nature (IUCN), 61% of the world’s bird species currently have declining populations.
Despite the severity of the problem, the authors highlighted practical solutions. Buildings can be designed to reduce bird collisions — and similar strategies could be used to minimise sound pollution.
“So many of the challenges we face with biodiversity loss feel inexorable,” said study co-author Neil Carter, also from the University of Michigan, “but we know how to use different materials and design structures to block sound.
The challenge is raising awareness and interest in implementing these solutions.”
The study underscores the importance of addressing human-induced noise as a critical factor in avian conservation and biodiversity protection, particularly in urban environments where birds are exposed to chronic sound disturbances.
