"Potentially harmful human-caused noise pollution affects nearly two-thirds of all protected areas in the United States, according to a report released on Thursday.
Researchers found that 63 percent of all U.S. protected lands are exposed to manmade noise from cars and activities like mining that is at least as twice as loud as ambient sounds from natural sources like wind, according to Colorado State University and the U.S. National Park Service.
'What we found was that a lot of the protected areas in the U.S. are pretty noisy,' said George Wittemyer, a professor at Colorado State University who oversaw the research. Wittemyer called the findings 'concerning.' "