Sounds in a National park
............The impact of noise on wildlife ranging from birds to whales to elk has been a growing focus of scientific study. Increasing evidence suggests that animals in natural settings modify their behavior, though sometimes only briefly, in response
to human commotion..........
One of the first things that a visitor to Muir Woods National Monument sees is a monitor that measures sound levels.....
Once the diesel engines had been stilled, visitors began falling into line, heeding a subtle signal that human noises are superfluous here.
But some of the signals are hardly subtle: signs posted near Cathedral Grove in the heart of the park call for silence. Near the entrance to the food and gift shop close to the park’s entrance, a decibel meter measures the sound of a visitor’s voice.
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