In addition to exhaust pollution (“Curb motorcycle pollution,” Oct. 16), the noise caused by motorcycles, and other vehicles, mufflered to emit the most noise possible is equally obnoxious.

It turns out that impurities and noise aren’t always bad things. We are always amazed that we live in a time where we are learning about the universe at such a fine level of detail.

Noise depends on how a protected area is managed, where a site is located and what kinds of activities take place nearby. For example, we found that protected areas managed by local government had ...