The depths of our oceans hide a unique living world that we barely understand – but these mysteries are already under threat from a controversial new industry: deep sea mining.

Lion’s Mane Jellyfish, a deep sea creatures found in the Arctic. © Alexander Semenov
A handful of companies and governments are planning to send monster machines deep beneath the waves, disrupting sensitive and unique habitats to extract metals and minerals. While licences have been granted to explore for deep sea mining in over a million square kilometres of our global oceans, no deep sea mining is happening – yet.
Sending gigantic mining machines designed to bulldoze and churn up the seabed is clearly a very bad idea. Want to know how bad? Here’s five reasons why deep sea mining will only get our planet into deep trouble.

A shoal of Almoco Jacks on the Dom João de Castro seamount, Azores.
Reason 1: Very bad news for wildlife
Scientists are warning that plundering the seafloor with monster machines risks inevitable, severe and irreversible environmental damage to our oceans and marine life. You only have to look at some of the names of recent research papers: ‘Deep-Sea Mining with No Net Loss of Biodiversity – An Impossible Aim’.
In the deep sea, we find underwater mountains that are oases for sea creatures, ancient coral reefs and sharks that can live for hundreds of years. These are among the longest living creatures on Earth, which makes them particularly vulnerable to physical disturbance because of their slow growth rates. Researchers estimate that harm to wildlife from mining “is likely to last forever on human timescales”.
As if the total destruction of their homes wasn’t bad enough, machines cutting the seafloor will create sediment plumes, which could smother deep sea habitats for kilometres. The ships on the surface for the mining operation could also release toxic vapours into the water, harming many ocean species for hundreds or even thousands of kilometres.
And it’s not just pollution wildlife have to worry about. Noise generated by churning machinery risks harming and disturbing marine mammals like whales, while floodlighting areas of the dark deep ocean could cause permanent disruption to sea creatures adapted to very low levels of natural light.

The spiral tube worm, or Sabella Spallanzanii, lives in membranous tubes, often reinforced by the inclusion of mud particles and has a feathery, filter-feeding crown that can be quickly withdrawn into the tube when danger threatens. © Greenpeace / Gavin Newman
Reason 2: Extinction of creatures found nowhere else on the planet
The creatures of the deep sea, specially adapted to live in the extreme alien environment of the ocean depths, almost look like something from another planet. From ‘zombie worms’ discovered in 2002, to a transparent anemone that can eat worms six times its own mass, the deep seas are full of weird and wonderful creatures. At one of the target sites for mining, 85% of the wildlife living around hydrothermal vents are found nowhere else in the oceans.
Shockingly, licences have already been granted to explore for mining potential at vents, including the incredible Lost City in the middle of the Atlantic. Mining machines grinding up and destroying the habitats that these creatures are specifically designed to live in means they could never recover – risking the extinction of unique species. The physical recovery of the nodules that mining companies want to extract takes millions of years, and we do not know if creatures dependent on nodules can recover after their removal.

A scyphozoan jellyfish found in the Arctic.
Reason 3: Disturbing one of our best allies against climate change
The deep sea is an incredibly important store of ‘blue carbon’, the carbon that is naturally absorbed by marine life, and which remains stored in deep sea sediment for thousands of years after these creatures die – helping to slow climate change.
But by impacting on natural processes that store carbon, deep sea mining could even make climate change worse. The disruption caused by the machines may release carbon stored in deep sea sediments, and the wider impacts could disrupt the processes that store carbon in those sediments.
We know that we are facing a climate emergency. Why would we make it worse for ourselves?!

Hercules captured this image of a deep-sea jelly fish, several meters above the seafloor just south of the IMAX vent at Lost City. © NOAA/OAR/OER
Reason 4: Impacting the ocean food chain
This widespread disruption to marine life would impact the whole ocean food chain. A Greenpeace investigation revealed that companies hoping to be involved in the supply chain are fully aware of this risk – a document circulated at a deep sea mining stakeholder meeting acknowledges “the potential extinction of unique species which form the first rung of the food chain.”

Coal mining near the Hambach Forest. Imagine a machine like this digging up the seabed.
Reason 5: Do we want to destroy wonders that we are yet to discover and properly understand?
So far, we’ve only explored 0.0001% of the deep seafloor to see what lives there. We have so much more to learn about the deep ocean’s wildlife and ecosystems. How can companies properly risk manage something that we are yet to fully understand? There could be many more risks than they are aware of, from opening a new industrial frontier in the largest ecosystem on Earth. Without proper protection of the deep sea, we could destroy species and ecosystems yet to even be discovered.
No minerals or metals are worth destroying ecosystems we don’t even understand yet. Companies that use these materials for smartphones and renewable energy should be investing in recycling and new technology instead of threatening marine life for profit.
It’s clear that deep sea mining would be very bad news for our oceans.
And the corporations that want to get going with this destructive practice know the risks. Just as the oil industry spent years downplaying the environmental risks of their product while convincing politicians it was essential for the economy, so now deep sea mining companies are trying to convince politicians they offer a “green solution”. This isn’t true.
Let’s not repeat our mistakes and let this risky industry get a grip on our deep seas. With the nature and climate crises that we are facing, the stakes are simply too high. We shouldn’t be asking ‘how much new harm will we allow?’ – we should be making ambitious plans to help our oceans recover to health.
To help make this happen we are building an unstoppable global movement for healthy oceans, to protect nature and tackle climate change. So far over 900,000 people globally have signed our petition, calling on governments to agree a Global Ocean Treaty next year, which can put vast areas off-limits to exploitation and raise environmental standards for any industrial activity in international waters, putting protection at the heart of how we collectively manage our global oceans. A strong Global Ocean Treaty can help protect the hidden treasures of the deep sea from reckless exploitation.
The deep sea is the largest ecosystem on Earth. We should protect it and learn from it, not mine it.
Join the movement and sign the petition for a strong Global Ocean Treaty.
Discussion
I have been campaigning for the environment since I was a teenager interested 1980's. I'm also a member of Friends of the Earth. These campaigns are imperative and I'm honoured to be a part of this. Elaine Fegan
Have we not damaged the planet enough without plundering the oceans as well, it is all about profit, we are too much of a throwaway society upgrading our phones etc every year , which puts our natural resources under huge pressure. we need to start conserving our planet and stop destroying it ,for our futures and our children's futures.
I was sad to read in the Australian financial revue 'Chantecleer' back page today that a so-called socially aware Australian entrepreneur by the name of Karl Siegling has invested $9million in a private company called DeepGreen Metals. This mining company is moving to industrial scale harvesting of high grade , polymetallic nodules from the ocean floor between Hawaii and Mexico, for crushing to produce nickel, copper, mangenese and cobalt for use in car batteries.
It's no good telling people not to do things. They have to be given an alternative. The heavy consumers of the west need a social incentive to live more sustainably.
I agree in this.movement
We all knew this was going to happen sooner or later and again people only start taking action once the planning has started and then the situation becomes volatile and convoluted. A few hours research on land mining is a great indicator of what is in store for the seabed and it is a grim reality with dire consequences. The environmental destruction caused by land mining is never in the media spotlight and you do not have to be a genius to work out why that is. Petitions and spending years debating at government levels will not stop this next faze of human complacency and it is just a matter of time before the companies who are now ready to commence the first stage of seabed mining are floating (no pun intended) on the stock exchange. Disruption is the only viable solution to stop this. Production support vessel’s will be in constant communication with the mining equipment on the sea bed and the most effective way to disrupt these systems is with the use of signal inhibitors (jammers). They can be incredibly effective if designed right and can be deployed instantly: Turn on, drop in ocean = Disruption. Further more these mining machines are also full of electronic components which can be seen as another disruption point. Our civilization survives in the complacency of cowardly or malignant minds, a sacrifice to the vanity of aging adolescents. Albert Camus
sounds good
Take action for your users because if you don't when they are gone so are you
These companies are vandals and destroyers. They do not care about the planet not the environment. Their reasons are pathetic and inexcusable
I have tried and tried to send a message to these companies and the send message now.... will not work
Hi Linda. You can add your name to protect the oceans here >> https://act.greenpeace.org/page/40938/petition/1
Please do not do anything else that could make the planet even harder to pull back from. Our children, grandchildren and many more generations will have enough to put right as it is. We can not leave them a worse world than it is already going to be, it is just not fair or alright.
"YOU YES YOU" ALL THE PEOPLE THAT HAVE ONE THING IN COMMON I CALL THEM NO-NO'S ,NO TOO THIS NO TOO THAT ,THE SAME PEOPLE WHO SAID NOT THAT LONG "NO" MOBILE PHONE MAST'S HERE? O THE SAME PEOPLE NOW COMPLAINING NO SIGNAL? THE SAME PEOPLE WITH MOBILE PHONE IN POCKET. AND WHERE DID THE THE SPECIAL MATERIALS COME FROM ??? I BELIEVE SEVEN TENTHS OF OUR LITTLE BALL IS OCEAN WE AS PEOPLE DO NOT ANY CHOICE BUT TO USE WHATEVER IT TAKES TO SURVIVE ON OUR LITTLE BALL COS WE AIN'T GOT NO WHERE ELSE TO GO ???TO ALL THE NO-NO'S
As long as the world population increases, we need more resources. A 100% recycling rate (currently impossible) will not change this. As mineral resources are limited and globally not fairly distributed, the development of new resources in new environments is inevitable. Developing countries (with high birth rates) also have the right to develop further, involving an increasing consumption of key metals contained in manganese nodules. Is manganese nodule mining less "sustainable" compared to land-based mining? We can't answer. Also, the interpretation of "sustainable" is spongy. However, I believe that we can harvest manganese nodules in a sustainable manner. What we need is a strong regulatory framework. I'm confident the ISA can do it.
The oceans must be saved!
I have red with interest all you statements but need to know much more about the situation before I commit myself. Is what they intend more beneficial to humans than to the fish? Is what they intend to do end the oceans as we know them today? We all know that what happens in the oceans has a lot to do with the planet's weather etc. But what would happen eventually. Margaret Hook
I don’t understand how any company can purchase any type Of licence. We or any country do not win the Ocean floor!
Please let us stop destroying and start protecting our beautiful planet. If not we are fast becoming the authors of our own demise. The ocean needs to be protected and we rely on you to ensure we get a strong global ocean treaty BEFORE any mining or exploration startas.
The incredible stupidity of it let alone besides the plain unnecessary avarice is completely opposite to the real needs of the plane, our one planet and life support. We should of course be preserving what we can of our already over exploited planet and making best use of the material we have already obtained from it