A new study in the May 5 issue of Science Magazine shows that human noise pollution has doubled in 63 percent of U.S. protected areas.

Why it matters:

1. Human disturbances are supposed to be reduced in these protected areas since they're specifically designed to be safe havens for biodiversity.
2. Noise pollution reduces the ability of prey to hear predators approaching, can interfere with finding mates, and can also affect plants if herbivores change their locations due to excess noise.

The good news: Species listed under the U.S. Endangered Species Act seem to be experiencing about a 56 percent lower noise excess than unprotected areas.

Where to focus mitigation efforts: The authors found that human transportation networks, development, and extraction (think: timber, mining, oil, and gas) correlated with a proximity to cities led to a high noise pollution. Plus, lands managed by local governments had the highest noise levels.