Noise a new threat to wildlife

A leading James Cook University scientist is calling attention to the disturbing impact of road noise on wildlife.

JCU’s Distinguished Research Professor and Australian Laureate Fellow Bill Laurance said a new paper by US researchers in the prestigious journal Proceedings of the National Academy of Sciences USA had disturbing implications.

The researchers from Boise State University strung loudspeakers along half a kilometre of untouched Idaho forest and played noise at the level found on a suburban street.

They discovered bird abundance decreased 31 percent compared to a similar area without traffic noise and the condition of the birds remaining decreased significantly. The investigators said birds never became accustomed to road noise. (Link to paper below).

Professor Laurance said the phantom-road study suggests that the rapidly expanding footprint of roads and other structures may be degrading habitats for noise-sensitive species.

“Species such as cassowaries that use low-frequency sound for communication may be especially vulnerable, with roads blocking or impeding their calls,” he said.

Professor Laurance said research showed even small dirt tracks reduced the abundance of bird species nearby, with major highways sometimes completely clearing areas of birdlife.

“Infrastructure is expanding at the fastest rate in human history. It’s already established that roads bring hunting, encroachment, wildfires and land speculation to forests and produce road kill and pollution. The new study again emphasizes the need to limit new roads in protected areas and ameliorate road noise from existing highways.”

Professor Laurance said there was no reason to think the findings would not also apply at sea and in the air. He said marine life may be disturbed by shipping lanes and high-intensity sonar, and birdlife distressed by aircraft noise and wind farms.