Almost two-thirds of mollusc species living around hydrothermal vents in the deep sea are at risk of extinction, according to new research that adds to concerns about the impact of seabed mining on biodiversity.
The study, led by Queen's University Belfast, has resulted in 184 mollusc species being added to the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species. These species are endemic to hydrothermal vents – hot springs on the ocean floor – and researchers said similar extinction risks would likely apply to other vent-dependent species such as crustaceans.
Lead researcher Elin Thomas warned that deep-sea mining companies seeking metals that form at the vents would destroy the habitat of these species, which have nowhere else to go. The International Seabed Authority (ISA) is meeting in Jamaica to finalise regulations by July 2023 that would permit undersea mining of cobalt, nickel and other metals.
Hydrothermal vents, found at depths of 2,000-4,000 metres, are biodiversity hotspots comparable to coral reefs, but each vent is only about a third the size of a football pitch. Of the 184 species assessed, 62% are listed as threatened, many in waters where mining licences have been granted, such as Japan and Papua New Guinea. The extinction threat is worst in the Indian Ocean, where every species is threatened and 60% are critically endangered.
