In this Oct. 20, 2008, file photo, tourists get out of a bus next to a viewing area at Yosemite National Park. Humans are creating noise pollution that poses a threat to wildlife and natural serenity, according to a new study, and vehicles such as buses produce such pollution.
In this Oct. 20, 2008, file photo, tourists get out of a bus next to a viewing area at Yosemite National Park. Humans are creating noise pollution that poses a threat to wildlife and natural serenity, according to a new study, and vehicles such as buses produce such pollution. Paul Sakuma AP
In this Oct. 20, 2008, file photo, tourists get out of a bus next to a viewing area at Yosemite National Park. Humans are creating noise pollution that poses a threat to wildlife and natural serenity, according to a new study, and vehicles such as buses produce such pollution. Paul Sakuma AP