Overview
- Conducted in the Clarion‑Clipperton Zone at about 4,000 meters depth, the multi‑year program paired replicated controls with before‑and‑after sampling and DNA taxonomy to isolate mining impacts from natural variability.
- Researchers cataloged 4,350 macrofaunal specimens spanning 788 species, many new to science, establishing the largest quantitative baseline for abyssal sediment biodiversity to date.
- Plume‑affected sites roughly 400 meters from the collector tracks showed no measurable decline in overall abundance but exhibited shifts in species dominance and community composition.
- The nodule‑collecting vehicle removed about the top 5 centimeters of seafloor where most macrofauna reside, directly eliminating organisms within its tracks.
- Authors say the results will inform International Seabed Authority rulemaking, and they report that The Metals Company viewed the findings before publication without having editorial control.