As a Canadian company plans to mine minerals from the bottom of the Pacific Ocean in the coming months, a new study published in the journal Nature Communications shows how sediment from mining in the ocean floor could be harmful to marine life.
Helena Hauss is part of a team of researchers who looked at the impact that deep-sea mining could have on marine organisms, particularly jellyfish, and the results of the study worry the researcher.
The sediment clouds caused by mining cause a level of stress that “could affect the growth and reproduction rate” of these marine animals which “could also die of starvation”, explained the co-author of the study to La Canadian Press.
His team exposed jellyfish to clouds of sediment collected at a depth of 4,000 meters in the Atlantic Ocean, in order to reproduce the effects of mining on the seabed.
“It’s a simple, straightforward experience. We took the animal, exposed it to stress and measured its response,” explained Helena Hauss.
“The jellyfish activated genes related to wound healing, innate immunity and respiration,” and their response “required a lot of energy, even though the jellyfish were not dying,” he said. said the director of marine ecology research at the Norwegian Research Center.
“You could also see with the naked eye that to get rid of the sediment, the jellyfish produced a lot of mucus, which is a defense mechanism. »
The amount of energy the jellyfish expend to shed sediment indicates they will likely need to feed more, but “it’s concerning because the ocean floor is a food-limited environment,” Ms.me Hauss.
The researcher explained that to her knowledge, this is the first study that focuses on the impact of future mining activities on pelagic organisms, therefore species such as jellyfish, which live between the surface of the water and the depths of the ocean.
Scientific knowledge of the impact of mines on pelagic organisms is very limited, but according to Helena Hauss, “we know that mines will have destructive consequences on benthos”.
Benthos are the invertebrates that inhabit the seabed.
To access minerals in the ocean floor, mining companies will have to dig into the habitat of these creatures.
“Once destroyed, their habitat will not recreate itself, these are habitats that took millions of years to form,” explained Mme Hauss.
“In my personal opinion, which does not necessarily reflect those of people in my organization,” added the scientist, “we do not have enough knowledge to move forward with mining in the oceans.”
A mining code that does not yet exist
The deep ocean, which begins 200 meters from the surface, is the world’s largest habitat and covers more than half of the Earth’s surface.
Most of the species that live there are still unknown to scientists and the organization Deep-Ocean Stewardship Initiative estimates that there could be up to 2 million marine species and more than 500 billion different types of micro- organisms in the deep ocean.
This habitat, essential to the regulation of the global climate, because it stores carbon dioxide and heat and maintains biodiversity, arouses the desire of mining companies, because it contains many minerals useful in the manufacture of electric vehicle batteries, copper, cobalt and nickel in particular.
In international waters, it is the International Seabed Authority, of which Canada is a part, which is responsible for establishing rules for mining.
But the ocean mining code is still under discussion and is expected to be adopted by 2025.
Even in the absence of clear rules, Vancouver-based Canadian miner The Metals Company (TMC) and Nauru, a small island nation in Oceania, have indicated they intend to mine in the floor of the Pacific Ocean from 2024.
Less damaging than landmines, according to TMC.
Recently, the president of TMC wrote an “open letter” addressed to “ocean conservation organizations.”
In his missive, Gerard Barron argues that for critical metals like lithium, nickel, cobalt and copper, nearly 500 new mines will need to open over the next 5 to 10 years to respond to the energy transition.
“This means we will have to extract more of these metals in the next 30 years than we have in all of human history,” he wrote.
He also explained, in his letter, that if his company chose to focus on the extraction of polymetallic nodules, minerals that lie on the ocean bed, it is because these have many advantages over minerals. terrestrial do not have.
“A single nodule project can produce four metals: nickel, copper, cobalt and manganese, which would require three separate new mines on land,” argued Gerard Barron.
According to him, mining on the ocean floor “will disrupt life less, both in terms of biomass and quantity of living species” than land mining.
He also said his company’s understanding of marine ecosystems is growing rapidly.
To those who believe that “current knowledge is insufficient for effective management of the marine environment”, he responds that “this assessment predates the set of data collected” by his company.
So far, the International Seabed Authority has issued more than 30 ocean mineral exploration licenses, but no mining licenses.
Explorations are taking place in an area of 4.5 million square kilometers between Hawaii and Mexico, at depths of up to 6,000 meters.