The voice of the ocean: the predominant sound is no longer that of biodiversity.

By: Samira Scoton
Ph.D. Student in Maritime Studies (PPGEM/EGN); MSc in International Security and Defense (PPGSID/ESG); Researcher at LSC/EGN and NEPEDI/UERJ; Lawyer (FND/UFRJ).

The activities performed by humans are interfering with marine life. This statement, by itself, is nothing new, since human activities in the ocean are part of our own history. In this month’s column, I would like to bring up the subject of anthropogenic underwater noise, that is, noise pollution caused by human activities in the ocean. In an article published in Science[1], in the first semester of 2021, it was pointed out that since the industrial revolution, the oceans have become substantially noisier.

The study points to two factors that intensify the problem: the development of activities related to energy production infrastructure, construction, ships, active sonar, seismic surveys, synthetic sounds, and acoustic deterrent devices, which increase anthropogenic sounds; and the reduction of sounds of biological origin (biophony) due to hunting, fishing, and habitat degradation.

Furthermore, climate change has also affected the natural sounds of biodiversity, interfering with physiology, behavior, food and, consequently, impacting the survival of species. It is not necessary to be an expert in logic or math to realize that this account does not match.

In the ocean, it is the sound that allows some species to survive. This is because sound propagates in a marine environment to reach greater distances and it is through it that marine animals, from invertebrates to large mammals (such as whales), including birds and reptiles, explore and interpret the environment, and also interact with other species. Due to the massive drop in the number of animals that produce sound, combined with anthropogenic noise and the effects of climate change, ocean soundscapes are changing and impacting marine biodiversity.

When we talk about communication through sound, we immediately think of whales. They communicate through sound, and there are studies regarding the sound frequency they need to reach for this communication to be possible. Also, starting from the idea that I always use that something is only valued and respected when it is known, I recommend that you listen to the whales’ singing. I leave a suggestion[2] at the end of this column for you to listen to the humpback’s song.

Anthropogenic noise interferes with biodiversity in such a way that the Science study suggested that it should be equated with the damage caused by carbon dioxide and organic pollutants (read sewage). Although sound noise is a pollutant of point origin, its damages are not punctual. However, when the causing sources are removed, its effects quickly diminish.

The choice of this theme was not by chance. Those who look at the sea to contemplate it, cannot imagine that below that view that can bring us so much peace, there is also a situation of chaos for part of the biodiversity. Noise pollution is caused, as already mentioned, mainly by infrastructure, construction, ships, active sonar, seismic surveys, synthetic sounds, and acoustic deterrent devices. In other words, the causes of this type of impact are not part of most people’s daily lives, in a way, making this problem less palpable.

If the United Nations Decade of Ocean Science for Sustainable Development[3] intends to follow its motto “the science we need for the ocean we want”, one of the goals cannot be prioritized over the other. So, it is up to this agenda to look out for those whose voices are literally being confused by the noise of human beings. More than that, it is up to this agenda has the potential to prioritize knowledge of these factors by people who have no idea what is going on. It can no longer be an agenda of scientists and diplomats talking inside closed walls in the same voice as always. New voices need to be heard.

Once the ocean can be considered as a possible source of expansion of human activities, the management of noise and activities needs to be implemented to prevent the situation from getting worse. For a healthy and resilient ocean to be possible, as the Decade of Ocean Science aims, technological solutions must be applied and developed not only for economic development but for sustainable development. In other words, perhaps more direct, the noise of human beings cannot be louder than the voices of nature. The sound of the ocean must prevail, and it is up to us to find ways to fix the damage we have caused so far.

[1] [1]DUARTE, Carlos M. et al. The soundscape of the Anthropocene ocean. Science. 05 fev 2021. DOI: 10.1126/science.aba4658

[2] Baleia Jubarte Project: https://www.baleiajubarte.org.br

[3] UN. Decade of Ocean Science for Sustainable Development. Available in: The Decade of Ocean Science for Sustainable Development (oceandecade.org)