Seabed Mining Threatens 60% of Vent Molluscs: IUCN

More than 60% of the mollusc species found only around deep-sea hydrothermal vents could be lost to planned seabed mining, the International Union for Conservation of Nature said, reviving its call for a moratorium as governments prepare to negotiate rules for the emerging industry.

The IUCN, which sets the global benchmark for species status, reported that 125 of the 201 vent-dwelling mollusc species it has catalogued now rank as threatened on its revised Red List. Extraction of critical minerals such as copper, cobalt and zinc would bury the ecosystems in sediment and eliminate habitats, the group said.

Many of the animals were identified within the past decade and survive only at vents, where volcanically heated water can reach 450°C before jetting through the seabed. Upwards of 200 mollusc species live nowhere else on Earth.

"Deep-sea mining would smother the entire ecosystem," said Chong Chen, IUCN Mollusc Specialist Group. "Allowing these species to go extinct could mean also losing biological solutions to future challenges in medicine, materials, and technology before we have even had the chance to discover them."

The findings arrive as the International Seabed Authority opens a July 13-31 session in Jamaica, where members will weigh a code governing commercial extraction beyond national jurisdiction. Scientists note that vent organisms have already informed work on biomineralization, nanoparticle production for solar cells and potential plastic substitutes.

The debate carries weight for Mexico's deep-sea mining position, a country that ranks 12th globally by marine area and sits beside the mineral-rich Clarion-Clipperton Zone. National reserves are estimated at 21Bt of polymetallic nodules. Mexico shifted from backing accelerated ISA regulation in July 2023 to joining 25 other nations in a moratorium bloc that November, and has said it will not endorse international licenses until adequate environmental studies are complete. The stance contrasts with Washington, where a July 2025 executive order has fast-tracked permitting for firms including The Metals Company and American Ocean Minerals in waters adjacent to Mexico's exclusive economic zone.

Recent field data have reinforced the environmental case. A study published in December found macrofaunal density fell 37% and species richness dropped 32% within two years of a mining machine disturbing the Clarion-Clipperton seabed, the largest experimental assessment of its kind. The five-year project tracked the removal of 3,000t of nodules from 4,280m and was commissioned by Nauru Ocean Resources, a subsidiary of The Metals Company.

The mollusc review is part of a wider Red List update on how specialized species are faring under mounting human pressure. "Life on Earth has adapted to survive in the most hostile and unusual habitats, but as pressures on biodiversity mount across the planet, even the creatures with the most ingenious survival strategies are under threat," IUCN Director General Grethel Aguilar said. "But there is a clear path out of the biodiversity crisis: nature conservation works."

Location matters to outcomes. More than 30 vent molluscs escaped threatened status because they inhabit marine protected areas closed to mining, among them the snail Provanna exquisita in the Mariana Arc of Fire National Wildlife Refuge. The Indian Ocean snail Lirapex felix, by contrast, is now critically endangered because of mining activity.