Scientists said they have seen the first signs of life returning to deep sea mining tracks carved into the abyssal seabed more than four decades ago, but warned on Wednesday that full recovery may be “impossible.”
The new research, published in the journal Nature, comes as countries argue over the creation of the world’s first mining code on deep sea extraction at a meeting of the International Seabed Authority (ISA) in Kingston, Jamaica.
Scientists and campaigners have long insisted that future industrial-level mining will threaten marine ecosystems.
Risks range from species extinctions and damage to the ocean food web, to the potential for exacerbating climate change by churning up sediment that stores planet-heating carbon.
In the latest research, scientists in Britain assessed the lasting impact of one of the oldest known mining tracks in the vast Clarion-Clipperton Zone (CCZ), stretching between Hawaii and Mexico in international waters.
At depths of more than 4,000 meters (13,000 feet), the seabed here is scattered with metal rich rocks known as “nodules” and is home to a huge number of strange and rare animals almost entirely unknown to science.
A 1979 test in the CCZ left a wide strip of seabed cleared of nodules and framed by deep tracks eight meters (26 foot) apart made by the mining machine.
In 2023, scientists surveyed the site and found these marks in the seafloor remained clearly visible.
“The numbers of many animals were reduced within the tracks but we did see some of the first signs of biological recovery,” said lead author Daniel Jones of the National Oceanography Center.
While small and more mobile creatures were seen within the mining area, larger-sized animals that are fixed to the seafloor were still “very rare,” he said.
The sediment plumes kicked up by the machines were not found to have had a lasting impact, according to the research.
The authors said that while more modern equipment could be designed to limit the impact on ocean wildlife, the likely scale of any mining operations if they went ahead meant “visible physical impacts of the collection can be assumed to last for at least many decades.”
They added that a full return of life in affected regions “may be impossible” with the removal of the nodules, which are themselves a habitat for marine animals.
More: https://phys.org/news/2025-03-deep-sea-impacts-visible-decades.html
https://www.nature.com/articles/s41586-025-08921-3