Marine biology

  • Article
    | Open Access

    Navigation and trajectory planning in environments with background flow, relevant for robotics, are challenging provided information only on local surrounding. The authors propose a reinforcement learning approach for time-efficient navigation of a swimmer through unsteady two-dimensional flows.

    • Peter Gunnarson
    • , Ioannis Mandralis
    •  & John O. Dabiri
  • Article
    | Open Access

    Satellite-derived chlorophyll data and Google Earth Engine (GEE) are used to introduce the first global map of coastal eutrophication potential as a GEE app. The prospects of the app being used as a global framework for eutrophication screening/monitoring are discussed.

    • Elígio de Raús Maúre
    • , Genki Terauchi
    •  & Michael DeWitt
  • Article
    | Open Access

    As corals struggle to survive under climate change, it is crucial to know whether they can withstand increasing seawater temperatures. Using a controlled thermal stress experiment across three divergent coral holobionts, this study examines metatranscriptomic responses to heat stress corresponding to the coral host, photosymbionts and associated microbiota.

    • Viridiana Avila-Magaña
    • , Bishoy Kamel
    •  & Mónica Medina
  • Article
    | Open Access

    Sea spray aerosol (SSA) are an important way through which oceans can influence the atmosphere’s radiative properties. Here, the authors present measurements taken over a 42,000 km ship cruise in the Atlantic and Pacific Ocean and show that SSA number concentrations vary over a 24-hour cycle, possibly linked to surface water bubble-bursting dynamics.

    • J. Michel Flores
    • , Guillaume Bourdin
    •  & Ilan Koren
  • Article
    | Open Access

    Phytoplankton form the base of the marine ecosystem but current ocean models used for climate change projections are too simple to assess potential changes in plankton community structure. This study analyses a complex ecosystem model with 35 phytoplankton types to evaluate the changes in phytoplankton community composition, turnover and size structure over the 21st century.

    • Stephanie A. Henson
    • , B. B. Cael
    •  & Stephanie Dutkiewicz
  • Article
    | Open Access

    Warming will affect marine plankton biomass, but also its diversity and community composition in poorly understood ways. Here, the authors model the spatial distribution of 860 marine plankton species from 10 functional groups and identify the future hotspots of climate change impacts under RCP8.5.

    • Fabio Benedetti
    • , Meike Vogt
    •  & Nicolas Gruber
  • Article
    | Open Access

    Over the past century, the Western Antarctic Peninsula has experienced rapid warming and a substantial loss of sea ice with important implications for plankton biodiversity and carbon cycling. Using a 5-year DNA metabarcoding dataset, this study assesses how interannual variability in sea-ice conditions impacts biodiversity and biological carbon fluxes in this region.

    • Yajuan Lin
    • , Carly Moreno
    •  & Nicolas Cassar
  • Article
    | Open Access

    The motion of the ocean transports microorganisms, pollutants, and other particles, but these are challenging to track. Here the authors present a Lagrangian form of Betweenness Centrality which identifies bottlenecks in dynamical systems and fluid flows as well as an interpretation of diversity hotspots.

    • Enrico Ser-Giacomi
    • , Alberto Baudena
    •  & Emilio Hernández-García
  • Article
    | Open Access

    Silica formation in diatoms is of interest for a range of different subjects from biomimetics to oceanography. Here the authors study the formation of silicified extensions in diatoms and find that unlike cell wall elements, that form in the cytoplasm, the extensions have a different formation mechanism outside the cytoplasm.

    • Boaz Mayzel
    • , Lior Aram
    •  & Assaf Gal
  • Article
    | Open Access

    How acute deoxygenation events affect tropical marine ecosystems remains poorly understood. This study integrates analyses of coral reef benthic communities with microbial community sequencing to show how a deoxygenation event rapidly altered a shallow tropical coral reef ecosystem in the Caribbean.

    • Maggie D. Johnson
    • , Jarrod J. Scott
    •  & Andrew H. Altieri
  • Article
    | Open Access

    Nitrogen fixation by diazotrophs is critical for marine primary production. Using Tara Oceans datasets, this study combines a quantitative image analysis pipeline with metagenomic mining to provide an improved global overview of diazotroph abundance, diversity and distribution.

    • Juan José Pierella Karlusich
    • , Eric Pelletier
    •  & Rachel A. Foster
  • Article
    | Open Access

    Up to 40% of the ocean’s fixed nitrogen is lost in oxygen minimum zones (OMZs) by anammox, but despite the importance of this process, nitrogen loss patterns in OMZs are difficult to predict. Here the authors show that ammonium release from small particles is a major control of anammox in the Peruvian OMZ.

    • Clarissa Karthäuser
    • , Soeren Ahmerkamp
    •  & Marcel M. M. Kuypers
  • Article
    | Open Access

    The macroalgae Sargassum has grown for centuries in the oligotrophic North Atlantic supported by natural nutrient sources and cycling. Here the authors show that changes in tissue nutrient contents since the 1980s reflect global anthropogenic nitrogen enrichment, causing blooms in the wider Atlantic basin.

    • B. E. Lapointe
    • , R. A. Brewton
    •  & P. L. Morton
  • Article
    | Open Access

    Marine snow is a major route through which photosynthetically fixed carbon is transported to the deep ocean, but the factors affecting flux are largely unknown. Here the authors use high frequency imaging of marine snow particles collected during phytoplankton blooms to categorize and quantify transport.

    • Emilia Trudnowska
    • , Léo Lacour
    •  & Lars Stemmann
  • Article
    | Open Access

    The COVID-19 response has led to unparalleled changes in the functioning of human society, from travel restrictions to changes in consumption. Here the authors use high resolution satellite data to track the global reduction in marine traffic during the pandemic, and more recent hints of recovery to pre-lockdown levels.

    • David March
    • , Kristian Metcalfe
    •  & Brendan J. Godley
  • Article
    | Open Access

    Warming ocean water plays a significant role in accelerating Arctic sea ice melt. Here the authors present detailed observations of warm water of Pacific origin entering and diving beneath the Arctic ocean surface, and explore the dynamical processes governing its evolution.

    • Jennifer A. MacKinnon
    • , Harper L. Simmons
    •  & Kevin R. Wood
  • Article
    | Open Access

    Microplastic pollution is a major threat to marine food webs, but the wider ranging impacts on global ocean biogeochemistry are poorly understood. Here the authors use an Earth system model to determine that zooplankton grazing on microplastics could exacerbate trends in ocean oxygen loss.

    • K. Kvale
    • , A. E. F. Prowe
    •  & A. Oschlies
  • Article
    | Open Access

    Extracting functional information from 16S rRNA data surveys would provide a valuable tool for large-scale functional ecology. Here, the authors use PICRUSt2 to infer metabolic functions from bacterial marker gene data across the South Pacific Ocean, and compare them with rate data, biomass estimators and predictions based on shotgun metagenomes.

    • Eric J. Raes
    • , Kristen Karsh
    •  & Anya M. Waite
  • Article
    | Open Access

    Primary productivity in the Southern Ocean plays an important role in the drawdown of atmospheric CO2, but phytoplankton growth is limited by iron. Here the authors show that iron from hydrothermal vents fuels massive phytoplankton blooms in the Southern Ocean that have recurred in the same location for decades.

    • Casey M. S. Schine
    • , Anne-Carlijn Alderkamp
    •  & Kevin R. Arrigo
  • Article
    | Open Access

    Southern Ocean productivity is a crucial component of the carbon cycle, but phytoplankton there are thought to be limited by iron. Here the authors conduct trace metal incubation experiments across the Drake Passage, finding that manganese can play an unexpected role in restricting phytoplankton growth.

    • Thomas J. Browning
    • , Eric P. Achterberg
    •  & Edward Mawji
  • Article
    | Open Access

    The Arctic Ocean is influenced by carbon and nutrients from rivers and erosion, but how this affects phytoplankton productivity is not understood. Here, the authors use a spatio-temporally resolved biogeochemical model to estimate that the input of carbon and nutrients fuels 28–51% of annual Arctic Ocean productivity.

    • Jens Terhaar
    • , Ronny Lauerwald
    •  & Laurent Bopp
  • Article
    | Open Access

    Climate change and local anthropogenic stressors threaten the persistence of coral reefs. Here the authors track coral bleaching over the course of a heatwave and find that some colonies recovered from bleaching while high temperatures persisted, but only at sites lacking in other strong anthropogenic stressors.

    • Danielle C. Claar
    • , Samuel Starko
    •  & Julia K. Baum
  • Article
    | Open Access

    It has been hypothesized that domestication can occur through the ‘commensal pathway’ in which the domesticate takes advantage of a niche created as a byproduct by the domesticator. Here, Brooker et al. provide evidence for a commensal domestication process between longfin damselfish and mysid shrimps.

    • Rohan M. Brooker
    • , Jordan M. Casey
    •  & William E. Feeney
  • Article
    | Open Access

    Zooplankton biomass in the dark ocean is thought to be low and weakly coupled to epipelagic primary production, but recent evidence suggests otherwise. Here the authors analyse data from the Malaspina Circumnavigation Expedition and published data to estimate bathypelagic zooplankton biomass and assess its relationship to primary production, currently not well accounted for in oceanic C budget.

    • S. Hernández-León
    • , R. Koppelmann
    •  & C. M. Duarte
  • Perspective
    | Open Access

    Marine aquaculture is widely proposed as compatible with ocean sustainability, biodiversity conservation, and human nutrition goals. In this Perspective, Belton and colleagues dispute the empirical validity of such claims and contend that the potential of marine aquaculture has been much exaggerated.

    • Ben Belton
    • , David C. Little
    •  & Shakuntala H. Thilsted
  • Article
    | Open Access

    Fish production is predicted to decrease with anthropogenic global warming. Here the authors analyse fish fossil assemblages from 62–46 My old deep-sea sediments and instead find a positive correlation between fish production and ocean temperature over geological timescales, which a data-constrained model explains in terms of trophic transfer efficiency and primary production.

    • Gregory L. Britten
    •  & Elizabeth C. Sibert
  • Article
    | Open Access

    Phytoplankton are biogeochemically important but the drivers of their seasonal cycles in the Southern Ocean are poorly resolved. Here the authors use seven years of ARGO float data to measure bloom initiation, decline and termination throughout the Southern Ocean, finding that bloom dynamics are especially sensitive to the coupling between cell division rates and loss processes.

    • Lionel A. Arteaga
    • , Emmanuel Boss
    •  & Jorge L. Sarmiento
  • Article
    | Open Access

    Due to legislative shortfalls, species of global conservation concern can still be captured in commercial fisheries. Here the authors show that 91 threatened species are reported in catch/landing databases, 13 of which are traded internationally despite their conservation concern.

    • Leslie A. Roberson
    • , Reg A. Watson
    •  & Carissa J. Klein
  • Article
    | Open Access

    The blooming alga Emiliania huxleyi and its viruses are a model for density-dependent virulent dynamics. However, Knowles et al. show that this host–virus system exhibits temperate dynamics at natural host densities, in a manner dependent on host physiology.

    • Ben Knowles
    • , Juan A. Bonachela
    •  & Kay D. Bidle
  • Article
    | Open Access

    Ecosystem Based Management measures developed to prevent overfishing could be particularly important under climate change. Here the authors combine climate and fish stock modelling to show that EBM cap implementation reduces climate-driven fishery declines under RCP 4.5 and 8.5 before midcentury. However, there are thermal tipping points beyond which potential collapses are predicted.

    • K. K. Holsman
    • , A. C. Haynie
    •  & A. E. Punt
  • Article
    | Open Access

    Ocean cold seeps are poorly understood relative to related systems like hydrothermal vents. Here the authors use high pressure bioreactors and microbial communities from a cold seep mud volcano and find a previously missing step of methane conversion to acetate that likely fuels heterotrophic communities.

    • Shanshan Yang
    • , Yongxin Lv
    •  & Yu Zhang
  • Article
    | Open Access

    Brandl, Johansen et al. compare organismal traits, community structure, and productivity dynamics of cryptobenthic reef fishes across two locations, the Arabian Gulf and the Gulf of Oman, the former of which harbors the world’s hottest coral reefs. They show that environmental extremes in the Arabian Gulf result in dramatically less diverse, abundant, and productive cryptobenthic fish assemblages, which could foreshadow the future of coral reef biodiversity and functioning.

    • Simon J. Brandl
    • , Jacob L. Johansen
    •  & John A. Burt
  • Article
    | Open Access

    Anthropogenic stressors affect many aspects of marine organismal health. Here, the authors expose surgeonfish to temperature and pesticide stressors and show that the stressors, separately and in combination, have adverse effects on thyroid signaling, which disrupts several sensory systems and important predation defenses.

    • Marc Besson
    • , William E. Feeney
    •  & David Lecchini
  • Article
    | Open Access

    Little is known about gene expression of organisms in the deep sea, partially owing to constraints on sampling these organisms in situ. Here the authors circumvent this problem, fixing tissue of a deep-sea mussel at 1,688 m in depth, and later analyzing transcriptomes to reveal gene expression patterns showing tidal oscillations.

    • Audrey M. Mat
    • , Jozée Sarrazin
    •  & Marjolaine Matabos
  • Article
    | Open Access

    Satellites can observe marine phytoplankton, but observations are sparse in seasonally dark, cloudy environments like the Southern Ocean. These authors use Argo floats to track the fate of phytoplankton blooms off Antarctica and determine 10% of biomass is exported, while 90% is prey to grazing.

    • Sébastien Moreau
    • , Philip W. Boyd
    •  & Peter G. Strutton
  • Article
    | Open Access

    Numerous marine ecosystem models are used to project animal biomass over time but integrating them can be challenging. Here the authors develop a test for statistical significance in multi-model ensemble trends, and thus relate future biomass trends to current patterns of ecological and socioeconomic status.

    • Daniel G. Boyce
    • , Heike K. Lotze
    •  & Boris Worm
  • Article
    | Open Access

    It is unclear whether rapid climate change will alter the effectiveness of marine reserves. Here Graham et al. use a 20-year time-series from the Seychelles to show that marine reserves may not prevent climate-driven shifts in community composition, and that ecological responses to reserves are substantially altered.

    • Nicholas A. J. Graham
    • , James P. W. Robinson
    •  & Shaun K. Wilson
  • Article
    | Open Access

    Global environmental changes threaten many food-producing sectors, including aquaculture. Here the authors show that countries most vulnerable to climate change will probably face the highest antimicrobial resistance in aquaculture-related bacteria, and that infected aquatic animals have higher mortality at warmer temperatures.

    • Miriam Reverter
    • , Samira Sarter
    •  & Rodolphe E. Gozlan
  • Article
    | Open Access

    Corals have evolved as finely tuned light collectors. Here, the authors report on the 3D printing of coral-inspired biomaterials, that mimic the coral-algal symbiosis; these bionic corals lead to dense microalgal growth and can find applications in algal biotechnology and applied coral science.

    • Daniel Wangpraseurt
    • , Shangting You
    •  & Silvia Vignolini
  • Article
    | Open Access

    The North Atlantic current has been suspected to trigger intrusions of temperate marine species in the Arctic. Here, Oziel and colleagues reveal the link between the poleward intrusion of the temperate coccolithophore Emiliania huxleyi and the North Atlantic current, showing evidence for bio-advection as an important mechanism.

    • L. Oziel
    • , A. Baudena
    •  & M. Babin
  • Article
    | Open Access

    Eddies are common ocean features that isolate large swaths of seawater, but it is unclear how they influence productivity of phytoplankton trapped inside. Here Ellwood and colleagues use stable and radiogenic isotopes to characterize a Southern Ocean eddy, finding vanishingly low iron concentrations that drive low productivity across the region.

    • Michael J. Ellwood
    • , Robert F. Strzepek
    •  & Philip W. Boyd
  • Article
    | Open Access

    Biogeographic patterns of genetic diversity are poorly documented, especially for fish species. Here the authors show that (mitochondrial) genetic diversity has global spatial organization patterns with different environmental drivers for marine and freshwater fishes, where genetic diversity is only partly congruent with species richness.

    • Stéphanie Manel
    • , Pierre-Edouard Guerin
    •  & Loïc Pellissier
  • Article
    | Open Access

    Increasingly, eDNA is being used to infer ecological interactions. Here the authors sample eDNA over 18 months in a marine environment and use co-occurrence network analyses to infer potential interactions among organisms from microbes to mammals, testing how they change over time in response to oceanographic factors.

    • Anni Djurhuus
    • , Collin J. Closek
    •  & Mya Breitbart
  • Article
    | Open Access

    The relationship between the coral animal and symbiotic algae is essential to coral health, and researchers are turning to Exaiptasia, a model cnidarian system, to study this relationship mechanistically. Here the authors find that endosymbiotic algae become limited by nitrogen at high population densities and provide the host with high levels of fixed carbon.

    • Tingting Xiang
    • , Erik Lehnert
    •  & Arthur R. Grossman
  • Article
    | Open Access

    Healthy coral reefs have an acoustic signature known to be attractive to coral and fish larvae during settlement. Here the authors use playback experiments in the field to show that healthy reef sounds can increase recruitment of juvenile fishes to degraded coral reef habitat, suggesting that acoustic playback could be used as a reef management strategy.

    • Timothy A. C. Gordon
    • , Andrew N. Radford
    •  & Stephen D. Simpson
  • Review Article
    | Open Access

    Swarms of crustaceans called krill dominate Antarctic ecosystems, yet their influence on biogeochemical cycles remains a mystery. Here Cavan and colleagues review the role of krill in the Southern Ocean, and the impact of the krill fishery on ocean fertilisation and the carbon sink.

    • E. L. Cavan
    • , A. Belcher
    •  & P. W. Boyd