Submarine mining carries an underestimated and invisible risk: noise in the depths of the ocean, which will bring ecological consequences in cascade, altering the biodiversity and the behaviors and physiological processes of many species.
An analysis of more than 2,800 studies conducted in the Clarion-Clipperton Zone (CCZ) —a vast submarine plain the size of India located in the Pacific Ocean, between Hawaii and Mexico— revealed that most of the animal classes that inhabit it are sound-sensitive.
However, the effects of noise pollution have only been studied in 35% of that biodiversity, according to the article to be published in the September issue of Marine Pollution Bulletin.
The area, dotted with bright black rocks, is the world’s largest mineral exploration region, rich in polymetallic nodules containing cobalt, nickel, manganese, and rare earth elements.
Are we putting marine life at risk with submarine mining?
For the industry, exploiting these deposits is the key to the energy transition; for governments, it is the epicenter of a global dispute; and for the scientific community, it is a matter that, in the light of growing evidence, demands a precautionary approach.
“We knew we wouldn’t find data about what’s in the deep sea, but what surprised me was the scarcity of information even in shallower waters,” admitted in an interview with SciDev.Net Travis Washburn, associate professor at Texas A&M University and one of the authors of the study.
“The issue, simply put, is a big unknown most of the time,” he emphasized.
He and his colleagues concluded that all taxonomic groups for which there are backgrounds with an acoustic perspective have some degree of susceptibility to noise, with impacts ranging from physiological alterations to changes in behavior.
In particular, they emphasize that up to a third of the fish species in the CCZ could be sound-sensitive.
According to co-author Lucille Chapuis, an expert in marine bioacoustics affiliated with La Trobe University in Melbourne, Australia, this means that they “use sound for everything: to communicate, find mates, avoid predators, find food… If we add noise to the system, these functions can be disrupted”.
Scientific discoveries of oceanic impact
Such findings present a significant bias, in that 72% of the publications they reviewed focused on mammals and fish species.
“Invertebrates are massively underrepresented. Despite forming the majority of the biodiversity in the CCZ, we do not know how they respond to sound or if they are even capable of perceiving it,” warns Chapuis.
Knowledge gaps are also evident in the lack of transparency from mining companies. “Literally, there is no public data on the noise levels of their activities… Everything is confidential…
So we have used many coastal indicators to obtain an approximate estimate,” adds Washburn.
For Daniel Cáceres, a Peruvian specialist in ocean governance who did not participate in the research, the most relevant aspect of this is that it demonstrates that the impact of mining in the CCZ is not distant or abstract: “sound waves could affect migratory species, regional food chains, and ecosystems that have ecological connections with the coasts of Latin America”.
Cáceres told SciDev.Net in an email that the study introduces a new category of ecological vulnerability, which goes beyond the physical understanding of sound, delving into its biological and evolutionary dimension, something that previous assessments do not consider with enough depth.
The marine biologist and regional representative of the Sustainable Ocean Alliance adds that it is “a didactic and strategic tool that helps to clearly explain why deep-sea mining is incompatible with conservation commitments… and emphasizes, for the umpteenth time, the need for the moratorium request that Latin America is leading”.
The contribution of Chapuis, Washburn, and collaborators coincides with a critical moment for deep-sea mining and with the launch, this week, of the first global political coalition to reduce harmful underwater noise pollution by 37 countries at the United Nations Conference on Oceans held in Nice, southern France.
Deep-sea mining is on the rise
The High Ambition Coalition for a Quiet Ocean commits to supporting policies that promote the design of quieter ships, establish marine protected areas, and support the development of capacities to assess and reduce oceanic noise.
In his address to the conference, United Nations Secretary-General António Guterres warned that unregulated deep-sea mining could turn the ocean into a lawless “wild west”.
To date, the International Seabed Authority (ISA) has granted 31 exploration licenses —17 of them in the CCZ— and is under pressure to approve a code that would allow commercial exploitation.
However, more than 30 countries, including several from Latin America, oppose this extractive race, such as submarine mining. Supported by the precautionary principle, they argue that industrial activities with high impact should not be allowed without solid scientific evidence guaranteeing that there will be no irreversible damage.
“The challenge now is to get humanity to agree to protect a heritage that belongs to everyone… these are ecosystems we don’t even know, where we would be destroying life forms we have not yet discovered”.
Alejandro Olivera, Mexico representative of the Center for Biological Diversity
Alejandro Olivera, Mexico representative of the Center for Biological Diversity, explained to SciDev.Net that, alongside these discussions, President Donald Trump issued an executive order in April of this year for the United States —which is not a member, but an observer at the ISA— to advance in the <a href="https://noticiasambientales.com/medio-ambiente/polemica-medida-trump-impulsa-la-ex
