A review of the International Seabed Authority database DeepData from a biological perspective: challenges and opportunities in the UN Ocean Decade.

There is an urgent need for high-quality biodiversity data in the context of rapid environmental change. Nowhere is this need more urgent than in the deep ocean, with the possibility of seabed mining moving from exploration to exploitation, but where vast knowledge gaps persist. Regions of the seabed beyond national jurisdiction, managed by the International Seabed Authority (ISA), are undergoing intensive mining exploration, including the Clarion-Clipperton Zone (CCZ) in the Central Pacific. In 2019, the ISA launched its database 'DeepData', publishing environmental (including biological) data. Here, we explore how DeepData could support biological research and environmental policy development in the CCZ (and wider ocean regions) and whether data are findable, accessible, interoperable and reusable (FAIR). Given the direct connection of DeepData with the regulator of a rapidly developing potential industry, this review is particularly timely. We found evidence of extensive duplication of datasets; an absence of unique record identifiers and significant taxonomic data-quality issues, compromising FAIRness of the data. The publication of DeepData records on the OBIS ISA node in 2021 has led to large-scale improvements in data quality and accessibility. However, limitations in the usage of identifiers and issues with taxonomic information were also evident in datasets published on the node, stemming from mismapping of data from the ISA environmental data template to the data standard Darwin Core prior to data harvesting by OBIS. While notable data-quality issues remain, these changes signal a rapid evolution for the database and significant movement towards integrating with global systems, through the usage of data standards and publication on the global data aggregator OBIS. This is exactly what has been needed for biological datasets held by the ISA. We provide recommendations for the future development of the database to support this evolution towards FAIR. Database URL https://data.isa.org.jm/isa/map.

Simulating pathways of subsurface oil in the Faroe-Shetland Channel using an ocean general circulation model.

Little is known about the fate of subsurface hydrocarbon plumes from deep-sea oil well blowouts and their effects on processes and communities. As deepwater drilling expands in the Faroe-Shetland Channel (FSC), oil well blowouts are a possibility, and the unusual ocean circulation of this region presents challenges to understanding possible subsurface oil pathways in the event of a spill. Here, an ocean general circulation model was used with a particle tracking algorithm to assess temporal variability of the oil-plume distribution from a deep-sea oil well blowout in the FSC. The drift of particles was first tracked for one year following release. Then, ambient model temperatures were used to simulate temperature-mediated biodegradation, truncating the trajectories of particles accordingly. Release depth of the modeled subsurface plumes affected both their direction of transport and distance travelled from their release location, and there was considerable interannual variability in transport.

High resolution study of the spatial distributions of abyssal fishes by autonomous underwater vehicle.

On abyssal plains, demersal fish are believed to play an important role in transferring energy across the seafloor and between the pelagic and benthic realms. However, little is known about their spatial distributions, making it difficult to quantify their ecological significance. To address this, we employed an autonomous underwater vehicle to conduct an exceptionally large photographic survey of fish distributions on the Porcupine Abyssal Plain (NE Atlantic, 4850 m water depth) encompassing two spatial scales (1-10 km(2)) on and adjacent to a small abyssal hill (240 m elevation). The spatial distributions of the total fish fauna and that of the two dominant morphotypes (Coryphaenoides sp. 1 and C. profundicolus) appeared to be random, a result contrary to common expectation but consistent with previous predictions for these fishes. We estimated total fish density on the abyssal plain to be 723 individuals km(-2) (95% CI: 601-844). This estimate is higher, and likely more precise, than prior estimates from trawl catch and baited camera techniques (152 and 188 individuals km(-2) respectively). We detected no significant difference in fish density between abyssal hill and plain, nor did we detect any evidence for the existence of fish aggregations at any spatial scale assessed.