Skip to main content

Noise in the National Parks

Researchers discuss how human-generated noise affects the natural world—and us.
(Photo: Pablo Hidalgo/Shutterstock)

(Photo: Pablo Hidalgo/Shutterstock)

Global warming, clean water, and growing global population are some of today's most pressing environmental issues. That list should be updated, it seems, as noise and light pollution have become major global concerns, a panel of researchers said on Monday.

Both noise pollution and light pollution have actually been pressing issues for a while, though they haven't received the attention of other environmental causes. That may change, however, with a set of new studies and reports on background noise and light from cars, airplanes, and other sources both in parks and around the country.

"Both noise and light pollution are growing far faster than the human population in the United States—they're somewhere between doubling and tripling every 30 years."

"The Park Service regards both the night sky environment and the natural sound environment as physical resources that must be protected under the [National Park Service] Organic Act of 1916," says Kurt Fristrup, a senior scientist at the Park Service's Division of Natural Sounds and Night Skies. The Organic Act explains that all resources must be left "unimpaired for the enjoyment of future generations."

"Applying that to acoustics is a rather new thing," Fristrup says, but sound is as much a part of the "expansive experience" of a National Park as the views. Fristrup and his team deployed 600 sound meters in parks to record noise and combined that with additional data from airport noise monitors. Then, Fristrup's group used a computer model to estimate how much background noise there would be at any point in the United States.

"Where we are heading with this research is to begin to understand just what are the opportunities and costs of those elevated background sound levels due to noise," Fristrup says. "Both noise and light pollution are growing far faster than the human population in the United States—they're somewhere between doubling and tripling every 30 years."

Increases in "this ubiquitous sensory pollution that is noise pollution" can have significant negative effects on the natural environment, says Cal Poly biologist Clinton Francis, whose work takes advantage of the fact that some natural gas wells employ "very noisy" pumping systems to study a variety of effects on species distribution, animal behavior, and community-level ecological processes. For example, the Western Scrub Jay distributes a "foundational" southwestern seed of the Piñon Pine tree group, but it appears as if "noise pollution is causing a large-scale decline in Piñon Pine seed dispersal."

Not all the effects are exactly bad, though. Hummingbirds seem to like the noise, aiding the pollination of flowers in noisier areas, though noise is generally bad for birds. "Impacts on birds are pretty severe," Francis says, in a wide variety of environments.

Still, Fristrup says, combatting noise and light pollution is within our reach. For example, Yellowstone National Park worked with environmentalists and snowmobilers to reach a "reasonable compromise," which allowed winter tour operators to bring more people into the park on the condition that they cut their vehicles' carbon emissions and reduce noise.