Calls of the Wild
(1,000–11,000 hertz)
To check your health, a doctor might listen to your heart beat and lungs fill with air. It turns out sound can register a lot about the health of an ecosystem, too.
Researchers in Queensland, Australia, assessed the condition of fragmented eucalyptus forests at 10 sites using conventional measures — including the size of forest patches, vegetation characteristics and the number of bird species detected — and sound recordings. They found that the more prevalent the human-generated sounds, such as traffic, machinery and voices, the poorer the ecological condition.
The researchers concluded that sound can be a valuable, and relatively inexpensive, tool for assessing the ecological well-being of forest fragments.