Current commercial interests focus on the massive sulphides around inactive hydrothermal sites at bathyal depths in the territorial waters of New Zealand and Papua New Guinea.154 Mining of massive sulphides at active vents would undoubtedly be harmful to the local vent communities.

However, the impacts of vent mining would differ dramatically from those of nodule mining because new vents would probably form quickly following mining and recolonization of local vent sites, once mining ceased, is expected to proceed rapidly.155 However, if sulphide mining targeted much larger areas or isolated geologic features with potentially endemic fauna such as calderas on seamounts, there could be a significant risk to biodiversity.