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New high-resolution datasets across La Jolla submarine fan, offshore California, illuminate low-relief, down-dip widening conduits emanating from a deep-sea channel that deposited a combination of laterally extensive sand strata seemingly crisscrossed by distributary patterns. Extensive coverage of this sector of the seafloor shows submarine-fan architecture and morphologies essentially different than distributary channelized patterns characteristic of subaerial systems and previous conceptual models of submarine fans. The main La Jolla channel, connected to La Jolla Canyon, loses confinement by widening, decreasing in relief, and developing scoured margins across kilometers-long down-slope and lateral distances. Two scales of distributary patterns are associated with sand-rich deposits down-system from, and outside of, fully formed channels. A larger-scale distributary pattern is identified in backscatter and bathymetry from trains of preferential erosion associated with laterally continuous repetitive steps that extend for kilometers outside channel confinement and may represent net erosional upper-flow-regime transitional bedforms. Smaller-scale distributary backscatter patterns in unconfined sand-rich deposits originate from the wide, low-relief channel. We suggest that the newly imaged La Jolla seascape displays sedimentary features that may be common on deep-sea fans but missed in previous lower resolution studies of submarine fans. Thus, La Jolla provides the basis for integrating previously enigmatic and (or) incomplete images of submarine fans. High-resolution seafloor, subsurface, and sample datasets highlight the importance of channel widening, headward erosion, and unconfined flows in La Jolla submarine-fan development, and may be relevant to other sandy submarine fan systems.

Remotely Operated Vehicles (ROVs) are essential to human-operated underwater expeditions in the deep sea. However, piloting an ROV to safely interact with live ecosystems is an expensive and cognitively demanding task, requiring extensive maneuvering and situational awareness. Immersive Virtual Reality (VR) Head-Mounted Displays (HMDs) could address some of these challenges. This paper investigates how VR HMDs influence operator performance through a novel telepresence system for piloting ROVs in real-time. We present an empirical user study [N=12] that examines common midwater creature capture tasks, comparing Stereoscopic-VR, Monoscopic-VR, and Desktop teleoperation conditions. Our findings indicate that Stereoscopic-VR can outperform Monoscopic-VR and Desktop ROV capture tasks, effectively doubling the efficacy of operators. We also found significant differences in presence, task load, usability, intrinsic motivation, and cybersickness. Our research points to new opportunities towards VR with ROVs.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Plastic waste has been documented in nearly all types of marine environments and has been found in species spanning all levels of marine food webs. Within these marine environments, deep pelagic waters encompass the largest ecosystems on Earth. We lack a comprehensive understanding of the concentrations, cycling, and fate of plastic waste in sub-surface waters, constraining our ability to implement effective, large-scale policy and conservation strategies. We used remotely operated vehicles and engineered purpose-built samplers to collect and examine the distribution of microplastics in the Monterey Bay pelagic ecosystem at water column depths ranging from 5 to 1000 m. Laser Raman spectroscopy was used to identify microplastic particles collected from throughout the deep pelagic water column, with the highest concentrations present at depths between 200 and 600 m. Examination of two abundant particle feeders in this ecosystem, pelagic red crabs (Pleuroncodes planipes) and giant larvaceans (Bathochordaeus stygius), showed that microplastic particles readily flow from the environment into coupled water column and seafloor food webs. Our findings suggest that one of the largest and currently underappreciated reservoirs of marine microplastics may be contained within the water column and animal communities of the deep sea.

Since its founding, the Monterey Bay Aquarium Research Institute (MBARI) has pioneered unique capabilities for accessing the deep ocean and its inhabitants through focused peer relationships between scientists and engineers. This focus has enabled breakthroughs in our understanding of life in the sea, leading to fundamental advances in describing the biology and the ecology of open-ocean and deep-sea animals. David Packard’s founding principle was the application of technological advances to studying the deep ocean, in part because he recognized the critical importance of this habitat in a global context. Among other fields, MBARI’s science has benefited from applying novel methodologies in molecular biology and genetics, imaging systems, and in situ observations. These technologies have allowed MBARI’s bioluminescence and biodiversity laboratory and worldwide collaborators to address centuries-old questions related to the biodiversity, behavior, and bio-optical properties of organisms living in the water column, from the surface into the deep sea. Many of the most interesting of these phenomena are in the midwater domain—the vast region of ocean between the sunlit surface waters and the deep seafloor.