Deep-sea mining poses new threat to sharks, rays and ghost sharks

Deep-sea mining poses new threat to sharks, rays and ghost sharks
by Clarence Oxford
Los Angeles CA (SPX) Oct 06, 2025

New research from the University of Hawai'i at Manoa reveals that thirty species of sharks, rays, and chimaeras - also called ghost sharks - could be directly affected by proposed deep-sea mining operations. Published in Current Biology, the study found that nearly two-thirds of these species are already listed as threatened with extinction, and mining activities could intensify their decline.

Lead author Aaron Judah, an oceanography graduate student at UH Manoa's School of Ocean and Earth Science and Technology (SOEST), warned that "deep-sea mining is a new potential threat to this group of animals which are both vital in the ocean ecosystem and to human culture and identity." Judah hopes that spotlighting this risk and proposing conservation pathways will help safeguard these species for future generations.

Working with an international research team, Judah overlaid maps from the IUCN Shark Specialist Group with deep-sea mining contract zones and reserves designated by the International Seabed Authority. The scientists also analyzed each species' reproductive habits and depth ranges to assess their exposure. Species that lay eggs on the seafloor, such as skates and chimaeras, are especially vulnerable to mechanical disruption from mining vehicles.

Among the thirty species studied were well-known ocean giants like whale sharks, manta rays, and the rare megamouth shark, as well as deep-sea specialists such as the pygmy shark, chocolate skate, and point-nosed chimaera. The study revealed that all thirty could be impacted by sediment discharge plumes, while twenty-five are at risk from direct seafloor disturbance. For many species, mining may affect more than half of their total depth range.

The Clarion-Clipperton Zone - a vast seabed region spanning from waters near Hawai'i to the eastern Pacific - is the most likely area for initial deep-sea mining operations. Senior author and SOEST oceanography professor Jeff Drazen noted that "sharks and their relatives are the second most threatened vertebrate group on the planet, mostly from overfishing. Because of their vulnerability, they should be considered in ongoing discussions of the environmental risks from deep-sea mining."

The authors recommend that monitoring programs and species assessments be included in environmental impact studies, and that marine protected areas be established to safeguard critical habitats. These measures could guide the International Seabed Authority and mining contractors in developing stronger conservation protocols.

Judah added that many shark and ray species are highly mobile and may traverse vast oceanic distances, potentially linking impacts from mining zones to ecosystems around Hawai'i. His ongoing work aims to identify additional species that may face similar risks from future mining projects.

Research Report:Deep-sea mining risks for sharks, rays, and chimeras