Seabed mining will have a devastating impact on deep sea fauna
The deep seafloor is teeming with life, most of which remains poorly known to science. It also constitutes an important reserve of natural resources, particularly minerals, that mining companies will start harvesting in the next few years. In this context, broad biodiversity assessments of deep-sea ecosystems are urgently needed to establish a baseline prior to mining. However, significant gaps in our taxonomic knowledge and the high cost of sampling in the deep sea limit the effectiveness of conventional morphology-based surveys.
In this article, we discuss the results of Laroche et al. (Mol Ecol, 2020). They capitalize on high throughput molecular methods to conduct one of the most detailed and rigorous surveys of the composition and biogeography of deep-seafloor metazoan communities to date. They show that deep seamounts in the Clarion Clipperton Zone are inhabited by rich metazoan communities that are distinct from those of the surrounding abyssal plains. These results have important conservation implications: if communities on deep seamounts were to persist after large-scale industrial mining operations on the surrounding plains, the seamounts would not serve as appropriate reservoirs to repopulate impacted areas.
Leray M. & Machida R. Seabed mining could come at a high price for a unique fauna. Molecular Ecology, 2020 In Press