When the going gets noisy, some birds get going; others thrive

Many birds really can't stand a racket. But when the going gets noisy, a few species of birds actually thrive, according to a new report published online on July 23rd in Current Biology, a Cell Press journal. The findings are particularly novel in that they document the effects of noise pollution on an entire breeding bird community rather than on particular species in isolation. They also suggest that it may be possible in some cases to mitigate the loss of bird diversity through better control of noise from highways, industrial complexes, and other sources.

"Noise pollution is an overlooked environmental problem that is now gaining attention with regards to the impact of noise on human wellbeing, plus its effects on wildlife," said Clinton Francis of the University of Colorado. "Though the impacts of noise pollution may pale in comparison to the problems of climate change and the loss and fragmentation of habitat, noise pollution is a strong force shaping communities in and around the growing number of human-dominated landscapes."

The researchers were able to isolate the effects of noise on bird communities in the new study by taking advantage of the existing natural gas extraction infrastructure that is common throughout the San Juan basin of northwestern New Mexico and southwestern Colorado. "Throughout this region, much of this infrastructure is located on public lands in fairly remote areas that are accessible only by small, dirt roads," Francis said. "Numerous gas wells are coupled with noise-generating compressors, which aid in the extraction and transportation of gas through pipelines."

Many other gas wells lack those noise-generating compressors but are very similar in all other respects. Francis's team was also able to turn the compressors off during their assessments of bird diversity. That was crucial because the noise could have biased the picture by causing researchers to miss birds.

They found that many species avoid nesting in noisy areas. However, some species appeared to be unaffected by noise and two others – the house finch and black-chinned hummingbird – were actually found to nest predominantly in noisier areas. Those unaffected by noise and noise-seekers succeed because a common nest predator, the western scrub-jay, tends to steer clear of the racket, Francis explained.

In the study area itself, humans' "noise footprint" could be controlled by building large walls around compressors, as is already done in residential settings, he said. Noise-controlling walls could also be built in other places, along busy roadways or surrounding other industries, he added. Specifically engineered road surfaces and tire treads could further reduce noise production.

Source: Cell Press