262 Voyages Beneath the Sea: a global assessment of macro- and megafaunal biodiversity and research effort at deep-sea hydrothermal vents

Abstract

For over 40 years, hydrothermal vents and the communities that thrive on them have been a source of profound discovery for deep-sea ecologists. These ecosystems are found throughout the world on active plate margins as well as other geologically active features. In addition to their ecologic interest, hydrothermal vent fields are comprised of metallic ores, sparking a nascent industry that aims to mine these metal-rich deposits for their mineral wealth. Here, we provide the first systematic assessment of macrofaunal and megafaunal biodiversity at hydrothermal vents normalized against research effort. Cruise reports from scientific expeditions as well as other literature were used to characterize the extent of exploration, determine the relative biodiversity of different biogeographic provinces, identify knowledge gaps related to the distribution of research effort, and prioritize targets for additional sampling to establish biodiversity baselines ahead of potential commercial exploitation. The Northwest Pacific, Southwest Pacific, and Southern Ocean biogeographic provinces were identified as high biodiversity using rarefaction of family-level incidence data, whereas the North East Pacific Rise, Northern East Pacific, Mid-Atlantic Ridge, and Indian Ocean provinces had medium biodiversity, and the Mid-Cayman Spreading Center was identified as a province of relatively low biodiversity. A North/South divide in the extent of biological research and the targets of hydrothermal vent mining prospects was also identified. Finally, we provide an estimate of sampling completeness for each province to inform scientific and stewardship priorities.

Population connectivity of the hydrothermal-vent limpet Shinkailepas tollmanni in the Southwest Pacific (Gastropoda: Neritimorpha: Phenacolepadidae)

“…Human exploitation of seafloor massive sulfides has recently become feasible and raised concerns about its impact on the diversity and persistence of the animal community [4,73]. Because any one vent ecosystem supports species with a range of dispersal potentials, vulnerability of the system may depend on the species with the shortest dispersal capacity.…”

“…Such animal communities are supported by primary production of chemosynthetic bacteria through grazing, suspension feeding, or symbioses at reducing environments [2]. Since the discovery of hydrothermal vents in 1977, more than 500 vent fields with the chemosynthetically nourished community have been found at Earth's submarine plate boundaries and several intraplate hot spots [3,4]. Despite being isolated and ephemeral in nature, these hydrothermal vents are characterized by a remarkable similarity of faunal assemblages within biogeographic regions [5].…”

Digenean parasites of deep-sea teleosts: A progress report

“…Nothing is known of the abyssal plain fauna anywhere other than the relatively small area of the Porcupine Abyssal Plain off southwestern Ireland. With the likelihood of imminent deep-sea mining, particularly of hydrothermal vent regions ( Thaler and Amon, 2019 ), it is probable that ‘habitat will be removed, sediment plumes will be created, and some biodiversity loss is inevitable … A fundamental problem for predicting the impacts of deep-sea mining on hydrothermal vents is our limited knowledge of these ecosystems in general’. These concerns are not solely applicable to hydrothermal vent systems but for the whole deep-sea, indeed the whole ocean.…”

Strengthening the global network for sharing of marine biological collections: recommendations for a new agreement for biodiversity beyond national jurisdiction

“…However, despite the fundamental importance of collections and biorepositories for research, they have received comparatively little attention in BBNJ negotiations and the literature, especially compared to ocean data, ocean observing, and related data practices (e.g. Levin et al , 2019 ; Pearlman et al , 2019 ; Snowden et al , 2019 ; Thaler and Amon, 2019 ). Information regarding existing collections capacities, from areas within and beyond national jurisdiction, could therefore inform questions pertaining to MGR in these negotiations.…”