Air pollution, water pollution. ocean acidification, etc. — We’ve all heard the dreaded terms grace widespread media attention before. These more sensational environmental damages tend to obscure other types from the public, despite their comparable harms. Issues such as light or thermal pollution are touched on rarely. But another is more inescapable, demanding to be addressed. It is now a permanent element of the bustling 21st century. If you live in a technologically-developed country or in any (sub)urban center, you’ve most definitely heard of it. Whenever you wake up it’s there: the jackhammers whirring, jets shooting above the skyline, drivers honking in frustration. It’s noise. While to us noise pollution may just be a simple annoyance that some good closed headphones can do away with, fragile ecosystems relying on silence and the audibility of natural sounds have little respite from human hum.
Whales and other cetaceans are common examples. Vocalization is a crucial part of intraspecies communication for these populations. Dolphins use certain calls/cues to indicate emotion, danger, and locations of other organisms. Their sounds are also unique identifiers of themselves and of different cetacean families.
But the increased use of military sonar in the oceans disrupts cetacean communication. An NOAA report correlated sonar use with nearby whale beaching events. Specifically, some whale songs are not innate and change during an individual’s lifetime to suit social needs; these are learned behaviors. Younger whales adapting to their language surroundings would have considerable trouble in the presence of these frequencies. Goldbogen et al. demonstrated that sonar detrimentally affects blue whales. The researchers used source levels less intense than that of military vessels, but still produced a sudden flight response. Pods would flee feeding and breeding areas to get away from the sonar source. In the midst, they would have extreme difficulty communicating. The whales lose precious locations and become victims of the more disastrous mass strandings along a nearby coastline.
But oceans are just a small part of a much larger problem. On land, the issue seems to worsen. Despite efforts to create safe havens, noise pollution pervades reservations still. The background noise comes from many sources: neighboring highways, tourism, resource extraction, airplanes overhead, etc. Colorado State researchers (Buxton et al.) reported that noise only further encroaches our national parks. Human-generated noise doubled background sound levels in 63% of protected areas while 21% received a tenfold increase, far above safe levels.
Perhaps the most sinister effect is the reduction of biodiversity. In one particular example, gas compressors, devices used in rail transport, scuba diving, etc., can directly affect insect population sizes according to the University of Florida. The results are classic biology; imbalanced populations endanger ecosystems to invasive species and distort predator–prey relationships. Grasshoppers, spiders, crickets and other crucial primary consumer insects reduced in population size. Dr. Akito Kawahara, co-author of the 2017 study, remarked saying:
Noise pollution affects all kinds of animals, and insects are no exception. They might be small, but they’re the dominant animals on the planet in terms of numbers. What happens to them affects whole ecosystems.
The situation both on land, and in the oceans seems dire, bearing no broad solutions. Noise will always be an element of human activity, so curbing it may be a much bigger issue than previously thought. Yet the situation is indeed reversible. Although no one can muffle human noise entirely, measures to reduce it are necessary. The same report by Buxton et al. observed that US protected areas with more stringent regulations on noise decreased background sound levels where some areas returned to safe ranges. More regulations at the national level posed by the NOAA or the EPA have the potential to be beneficial, but then the issue would likely get political. Regardless, noise pollution warrants human attention, for without intervention, we would have the next big environmental problem on our hands, if not already.
Read more on noise pollution here.
Editor: Rachel Levy