Repost of a column by park staff, printed in the Valley Courier, the local paper in nearby Alamosa, Colorado:

Have you ever heard the rustling sound of a bird’s wings flapping overhead…before you saw the bird? What about the sound of a rabbit chewing on a blade of grass? Most Americans don’t have the opportunity to hear those subtle sounds of nature at home, thanks to the backdrop of human-produced noises which drown them out.

Many people, however, say that the opportunity to hear natural sounds is an important reason to protect national parks, based on a 1998 study of the American public. And most respondents to a 1995 survey of national park visitors said that enjoying the sounds of nature and natural quiet were compelling reasons to visit national parks.

But-what exactly is ‘natural quiet’? Most of us would say that it’s the sounds of nature without an overlay of traffic, airplanes, machinery and other kinds of human-produced sounds. But anyone who has ever spent a windy night camping at the Dunes knows that windy nights might be ‘natural’…but they’re sure not ‘quiet’!

In order to learn just how quiet-or not–the natural world is at Great Sand Dunes National Park and Preserve, the National Park Service’s Natural Sounds Program installed a temporary acoustic monitoring station near the western edge of the national park in 2008. More acoustic data was collected in 2009, and we hope to learn more through future data collections. These studies are collecting information that’s both thought-provoking and just plain fun.

The fun stuff first: to listen to Great Sand Dunes elk bugling and coyotes singing, visit http://www.nature.nps.gov/naturalsounds/ and click on “Sound and Picture Gallery” on the left side of the page. “Elk” and “Coyote Chase” were both recorded at the acoustic station in Great Sand Dunes National Park.

And among the thought-provoking information suggested by the data: the west side of Great Sand Dunes National Park enjoys a very low existing ambient sound level: compared to sound levels that humans can hear and measure, it’s very, very quiet out there. That means that even very soft sounds can often be heard by a person with normal hearing. On the other hand, more than half of those audible sounds are not ‘natural’ in origin. For example, on the eight days that data was collected in 2008, aircraft sounds could be heard 56 percent of the time between 7 a.m. and 6 p.m. And an estimated 57 percent of all the sounds that were recorded were ‘extrinsic sounds’…that is, sounds that originate with humans and human activity.

So is it important to have access to the sounds of nature? Research into human and animal health and behavior says it is…and most of us would agree intuitively as well: being able to enjoy the world around us with all of our senses is an important part of our heritage. To learn more about sound, how it’s measured, and what it tells us about our environment, visit http://www.nature.nps.gov/naturalsounds/