Photo credit: Frédéric SALEIN licensed under CC BY-NC-SA 2.0

by Daniel Fink, MD, Chair, The Quiet Coalition

I recently wrote about a nighttime noise measurement just under 30 A-weighted decibels (dBA)* in the Huab Reserve in Namibia, but I can now report an even quieter nighttime noise measurement:

Only 28.3 dBA average sound pressure level, on the Tok Tokkie Trail in the even more remote NamibRand Nature Reserve, southern Africa’s largest private reserve.

NamibRand is also Africa’s first and only Gold Tier International Dark Sky Reserve, with the nearest small town having street lights located more than 130 km away. It is only the second place on the entire planet with the Gold Tier designation from the International Dark-Sky Association.

We were hiking on the Tok Tokkie trail, named after a common beetle in dry parts of southern Africa that attracts mates by knocking its abdomen on the ground. Maybe it wasn’t mating season, maybe the beetles weren’t knocking against the ground forcefully enough, for sure they were hurrying away from the sound of our footsteps, but we didn’t hear this sound. I don’t think that was because it’s too noisy there.

As I have written before, without anthropogenic noise, nature is quiet. The National Park Service noise maps show this. The National Park Service actually has a Natural Sounds and Night Skies Division that supports efforts at national parks and monuments to preserve natural sounds and dark skies. As this Division notes on its website:

The Natural Sounds and Night Skies Division supports NPS units system-wide by providing: scientific leadership to advance understanding and stewardship of natural sounds and night skies; highly specialized technical assistance; and development of policy and guidance to facilitate internal capacity building. More specifically, we provide assistance in collecting baseline data for ambient acoustic and night sky quality, identifying source specific impacts and engineered solutions to reduce, mitigate or prevent anthropogenic noise and excessive light in and around parks and national trails. We also assist with park planning, compliance, and external project reviews to help parks reduce impacts from noise and light pollution to natural and cultural resources and visitor enjoyment.

Those considerations shouldn’t apply just to national parks. They should be adopted by cities and states across the nation, obviously with adjustments needed for urban and suburban areas, transportation noise, etc. Loud noise isn’t natural, and it isn’t healthy but causes incontrovertible harm. That’s why I proposed a new definition of noise in 2019: “Noise is unwanted and/or harmful sound.”

A quieter world will be a better and healthier world for all.

*A-weighting adjusts sound pressure level measurements to approximate the frequencies heard in human speech.