"Park Service Surveys The Environment's Accoustical Health" [1]
The National Park Service has been documenting the acoustic environment in National Parks for years. But in addition to the sounds of nature -- Coyotes in Colorado, a hummingbird in Washington State, elk from Sand Dunes National Park -- the microphones also capture the sounds of civilization -- such as sirens.
Scientist Kurt Fristrup talks to NPR host Rachel Martin February 22, 2015. [2]
National (U.S.) [4]
Public [5]
Source: NPR [2], 02/23/2015