The Big Picture: Deep-sea mining poses a novel threat to marine biodiversity, particularly chondrichthyans. This study identifies 30 species at risk from mining activities in international waters, with nearly two-thirds already threatened with extinction.

Methodology: The researchers overlapped deep-sea mining exploration areas with species distributions and depth ranges. They analyzed spatial and depth overlap for different mining types (nodules, sulfides, crusts) and discharge plume scenarios.

The Discovery: 30 chondrichthyan species overlap with mining areas, 18 of which are already threatened. Most species (83%) overlap vertically with benthic mining impacts, while all species overlap with potential discharge plume scenarios.

Limitations: The study only considered mining in international waters, not exclusive economic zones. There are knowledge gaps around species distributions and ecology in the deep sea.

The Takeaway: Deep-sea mining could compound extinction risks for already threatened species. Precautionary management requires updated risk assessments, baseline monitoring, spatial protections, and discharge plume depth limits to safeguard biodiversity.

Source: 10.1016/j.cub.2025.09.019