Deep seabed mining on a commercial level in international waters could be allowed for the very first time later this year. However, the potential impact on sea creatures is still unknown.
Testing is already underway ahead of possible deep seabed mining in the Pacific. Image Credit: Marten van Dijl—Greenpeace.
Deep seabed mining, according to researchers from the University of Exeter and Greenpeace Research Laboratories, could pose a “significant risk to ocean ecosystems,” with “long lasting and irreversible” consequences.
The research concentrates on cetaceans (mammals like dolphins, whales, and porpoises) and concludes that more investigation is necessary to ascertain possible consequences.
Like many animals, cetaceans are already facing multiple stressors including climate change. Very little research has examined the impact that deep-sea minerals extraction would have on cetaceans. Cetaceans are highly sensitive to sound, so noise from mining is a particular concern.
Dr. Kirsten Thompson, University of Exeter
The experts highlight that the sounds generated by mining operations, including remotely operated vehicles on the seafloor, are almost certain to coincide with the frequencies at which cetaceans communicate.
We searched for data on how much noise such mining would cause, but no published assessment is available. We know noise pollution in the ocean is already a problem for cetaceans and introducing another industry that is expected to operate 24/7 would inevitably add to existing anthropogenic noise were deep seabed mining to go ahead. Despite this lack of information, it appears industrial-scale mining could soon begin in one of the planet’s few remaining undisturbed environments.
Dr. Kirsten Thompson, University of Exeter
The Clarion-Clipperton Zone (CCZ) in the Pacific Ocean, which is home to approximately 25 cetacean species, such as dolphins and sperm whales, is of specific importance to mining companies attempting to exploit polymetallic nodules.
Furthermore, mining companies are seeking seabed mineral resources near seamounts and deep-sea hydrothermal vents.
Seamounts are now known as important offshore habitats for some cetacean populations that forage or regroup around them but we still lack basic knowledge of these fragile ecosystems. In this context, it is very hard to assess the magnitude of the impacts of seamount seabed mining on the animals that live and feed around these structures.
Dr. Solène Derville, Oregon State University
Two-Year Rule
Even though the International Seabed Authority, a United Nations body, has approved 31 exploration permits for locations beyond national jurisdiction, no commercial-scale seabed mining has yet happened outside the exclusive economic zones (EEZs) of coastal nations.
But in June 2021, the Pacific Island of Nauru initiated the so-called “two-year rule” and notified the International Seabed Authority (ISA) of its intention to mine the deep sea, implying that mining could begin in June of this year, subject to whatever regulations the ISA has formulated by then.
Nauru is collaborating with The Metals Company, a Canadian company that has already started evaluating mining equipment in Pacific waters.
Dr. Thompson reasons, “Commercial-scale mining is expected to operate 24-hours a day, with multiple operations extracting minerals across an area of the seabed. We don’t know how this will affect cetaceans or the vast range of other marine species. What we do know is that it will be difficult to stop seabed mining once it has started. Given the imminent threat that the two-year rule presents to ocean conservation, we suggest there is no time to waste.”
Journal Reference
Thompson, K. F., et al. (2023) Urgent assessment needed to evaluate potential impacts on cetaceans from deep seabed mining. Frontiers in Marine Science. doi.org/10.3389/fmars.2023.1095930.