Coastal upwelling drives ecosystem temporal variability from the surface to the abyssal seafloor.

Long-term biological time series that monitor ecosystems across the ocean's full water column are extremely rare. As a result, classic paradigms are yet to be tested. One such paradigm is that variations in coastal upwelling drive changes in marine ecosystems throughout the water column.

ROV observations reveal infection dynamics of gill parasites in midwater cephalopods.

Gill parasites of coleoid cephalopods are frequently observed during remotely operated vehicle (ROV) dives in the Monterey Submarine Canyon. However, little knowledge exists on the identity of the parasite species or their effects on the cephalopod community. With the help of ROV-collected specimens and in situ footage from the past 27 years, we report on their identity, prevalence and potential infection strategy.

sp. nov. (Cnidaria, Scyphozoa, Coronatae, Atollidae): A New Species of Coronate Scyphozoan Found in the Eastern North Pacific Ocean.

We have observed and collected unusual specimens of what we recognize as undescribed types of the genus over the past 15 years. Of these, there appear to be three potentially different types. One of these has now been genetically sequenced and compared both morphologically and molecularly with five other species that have been found in the eastern Pacific.

A hybrid underwater robot for multidisciplinary investigation of the ocean twilight zone.

, an autonomous underwater vehicle, addresses specific unmet needs for observing and sampling a variety of phenomena in the ocean's midwaters. The midwater hosts a vast biomass, has a role in regulating climate, and may soon be exploited commercially, yet our scientific understanding of it is incomplete. has the ability to survey and track slow-moving animals and to correlate the animals' movements with critical environmental measurements.

Distribution, associations and role in the biological carbon pump of Pyrosoma atlanticum (Tunicata, Thaliacea) off Cabo Verde, NE Atlantic.

Gelatinous zooplankton are increasingly acknowledged to contribute significantly to the carbon cycle worldwide, yet many taxa within this diverse group remain poorly studied. Here, we investigate the pelagic tunicate Pyrosoma atlanticum in the waters surrounding the Cabo Verde Archipelago. By using a combination of pelagic and benthic in situ observations, sampling, and molecular genetic analyses (barcoding, eDNA), we reveal that: P.

Revealing enigmatic mucus structures in the deep sea using DeepPIV.

Many animals build complex structures to aid in their survival, but very few are built exclusively from materials that animals create . In the midwaters of the ocean, mucoid structures are readily secreted by numerous animals, and serve many vital functions. However, little is known about these mucoid structures owing to the challenges of observing them in the deep sea.

Bioluminescent backlighting illuminates the complex visual signals of a social squid in the deep sea.

Visual signals rapidly relay information, facilitating behaviors and ecological interactions that shape ecosystems. However, most known signaling systems can be restricted by low light levels-a pervasive condition in the deep ocean, the largest inhabitable space on the planet. Resident visually cued animals have therefore been hypothesized to have simple signals with limited information-carrying capacity.

Author Correction: The vertical distribution and biological transport of marine microplastics across the epipelagic and mesopelagic water column.

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

The vertical distribution and biological transport of marine microplastics across the epipelagic and mesopelagic water column.

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.

Pelagic shrimp play dead in deep oxygen minima.

Pelagic crustaceans are arguably the most abundant group of metazoans on Earth, yet little is known about their natural behavior. The deep pelagic shrimp Hymenopenaeus doris is a common decapod that thrives in low oxygen layers of the eastern Pacific Ocean. When first observed in situ using a remotely operated vehicle, most specimens of H.

Deep pelagic food web structure as revealed by feeding observations.

Food web linkages, or the feeding relationships between species inhabiting a shared ecosystem, are an ecological lens through which ecosystem structure and function can be assessed, and thus are fundamental to informing sustainable resource management. Empirical feeding datasets have traditionally been painstakingly generated from stomach content analysis, direct observations and from biochemical trophic markers (stable isotopes, fatty acids, molecular tools). Each approach carries inherent biases and limitations, as well as advantages.

From the surface to the seafloor: How giant larvaceans transport microplastics into the deep sea.

Plastic waste is a pervasive feature of marine environments, yet little is empirically known about the biological and physical processes that transport plastics through marine ecosystems. To address this need, we conducted in situ feeding studies of microplastic particles (10 to 600 μm in diameter) with the giant larvacean Larvaceans are abundant components of global zooplankton assemblages, regularly build mucus "houses" to filter particulate matter from the surrounding water, and later abandon these structures when clogged. By conducting in situ feeding experiments with remotely operated vehicles, we show that giant larvaceans are able to filter a range of microplastic particles from the water column, ingest, and then package microplastics into their fecal pellets.

New technology reveals the role of giant larvaceans in oceanic carbon cycling.

To accurately assess the impacts of climate change on our planet, modeling of oceanic systems and understanding how atmospheric carbon is transported from surface waters to the deep benthos are required. The biological pump drives the transport of carbon through the ocean's depths, and the rates at which carbon is removed and sequestered are often dependent on the grazing abilities of surface and midwater organisms. Some of the most effective and abundant midwater grazers are filter-feeding invertebrates.

Two eyes for two purposes: evidence for asymmetric vision in the cockeyed squids and .

The light environment of the mesopelagic realm of the ocean changes with both depth and viewer orientation, and this has probably driven the high diversity of visual adaptations found among its inhabitants. The mesopelagic 'cockeyed' squids of family Histioteuthidae have unusual eyes, as the left and right eyes are dimorphic in size, shape and sometimes lens pigmentation. This dimorphism may be an adaptation to the two different sources of light in the mesopelagic realm, with the large eye oriented upward to view objects silhouetted against the dim, downwelling sunlight and the small eye oriented slightly downward to view bioluminescent point sources.

Combined climate- and prey-mediated range expansion of Humboldt squid (Dosidicus gigas), a large marine predator in the California Current System.

Climate-driven range shifts are ongoing in pelagic marine environments, and ecosystems must respond to combined effects of altered species distributions and environmental drivers. Hypoxic oxygen minimum zones (OMZs) in midwater environments are shoaling globally; this can affect distributions of species both geographically and vertically along with predator-prey dynamics. Humboldt (jumbo) squid (Dosidicus gigas) are highly migratory predators adapted to hypoxic conditions that may be deleterious to their competitors and predators.

First in situ observations of the deep-sea squid Grimalditeuthis bonplandi reveal unique use of tentacles.

The deep-sea squid Grimalditeuthis bonplandi has tentacles unique among known squids. The elastic stalk is extremely thin and fragile, whereas the clubs bear no suckers, hooks or photophores. It is unknown whether and how these tentacles are used in prey capture and handling.

Vampire squid: detritivores in the oxygen minimum zone.

Vampire squid (Vampyroteuthis infernalis) are considered phylogenetic relics with cephalopod features of both octopods and squids. They lack feeding tentacles, but in addition to their eight arms, they have two retractile filaments, the exact functions of which have puzzled scientists for years. We present the results of investigations on the feeding ecology and behaviour of Vampyroteuthis, which include extensive in situ, deep-sea video recordings from MBARI's remotely operated vehicles (ROVs), laboratory feeding experiments, diet studies and morphological examinations of the retractile filaments, the arm suckers and cirri.

Oceanographic and biological effects of shoaling of the oxygen minimum zone.

Long-term declines in oxygen concentrations are evident throughout much of the ocean interior and are particularly acute in midwater oxygen minimum zones (OMZs). These regions are defined by extremely low oxygen concentrations (<20-45 μmol kg(-1)), cover wide expanses of the ocean, and are associated with productive oceanic and coastal regions. OMZs have expanded over the past 50 years, and this expansion is predicted to continue as the climate warms worldwide.

Conservation of deep pelagic biodiversity.

The deep ocean is home to the largest ecosystems on our planet. This vast realm contains what may be the greatest number of animal species, the greatest biomass, and the greatest number of individual organisms in the living world. Humans have explored the deep ocean for about 150 years, and most of what is known is based on studies of the deep seafloor.

Behaving in the dark: locomotor, chromatic, postural, and bioluminescent behaviors of the deep-sea squid Octopoteuthis deletron young 1972.

Visual behaviors are prominent components of intra- and interspecific communication in shallow-water cephalopods. Meso- and bathypelagic cephalopods were believed to have limited visual communication, other than bioluminescence, due to the reduced illumination at depth. To explore potential visual behaviors in mesopelagic squid, we used undersea vehicles to observe 76 individuals of Octopoteuthis deletron.

Invasive range expansion by the Humboldt squid, Dosidicus gigas, in the eastern North Pacific.

A unique 16-year time series of deep video surveys in Monterey Bay reveals that the Humboldt squid, Dosidicus gigas, has substantially expanded its perennial geographic range in the eastern North Pacific by invading the waters off central California. This sustained range expansion coincides with changes in climate-linked oceanographic conditions and a reduction in competing top predators. It is also coincident with a decline in the abundance of Pacific hake, the most important commercial groundfish species off western North America.