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Tag: Marine Science

  • Farming more seaweed to be food, feed and fuel

    Farming more seaweed to be food, feed and fuel

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    Newswise — A University of Queensland-led study has shown that expanding global seaweed farming could go a long way to addressing the planet’s food security, biodiversity loss and climate change challenges.

    PhD Candidate Scott Spillias, from UQ’s School of Earth and Environmental Science, said seaweed offered a sustainable alternative to land-based agricultural expansion to meet the world’s growing need for food and materials.

    “Seaweed has great commercial and environmental potential as a nutritious food and a building block for commercial products including animal feed, plastics, fibres, diesel and ethanol,” Mr Spillias said.

    “Our study found that expanding seaweed farming could help reduce demand for terrestrial crops and reduce global agricultural greenhouse gas emissions (GHG) by up to 2.6 billion tonnes of CO2-equivalent per year.”

    Researchers mapped the potential of farming more of the 34 commercially important seaweed species using the Global Biosphere Management Model.

    They estimated the environmental benefits of a range of scenarios based on land-use changes, GHG emissions, water and fertiliser use, and projected changes in species presence by 2050.

    “In one scenario where we substituted 10 per cent of human diets globally with seaweed products, the development of 110 million hectares of land for farming could be prevented,” Mr Spillias said.

    “We also identified millions of available hectares of ocean within global exclusive economic zones* (EEZs), where farming could be developed.

    “The largest share of suitable ocean was in the Indonesian EEZ, where up to 114 million hectares is estimated to be suitable for seaweed farming.

    “The Australian EEZ also shows great potential and species diversity, with at least 22 commercially viable species and an estimated 75 million hectares of ocean being suitable.”

    Mr Spillias said many native species of seaweed in Australian waters had not yet been studied from a commercial production perspective.

    “The way I like to look at this is to think about ancestral versions of everyday crops – like corn and wheat – which were uninspiring, weedy things,” he said.

    “Through thousands of years of breeding we have developed the staple crops that underpin modern societies and seaweed could very well hold similar potential in the future.”

    UQ study collaborator Professor Eve McDonald-Madden said the seaweed solution would have to be carried out with care, to avoid displacing problems from the land to the ocean.

    “Our study points out what could be done to address some of the mounting problems of global sustainability facing us, but it can’t be implemented without exercising extreme caution,” she said.

    This research was published in Nature Sustainability.

    UQ acknowledges the collaborative efforts of researchers from the International Institute for Applied Systems Analysis, CSIRO and the University of Tasmania.

    *An area of the sea in which a sovereign state has special rights regarding the exploration and use of marine resources, including energy production from water and wind.

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    University of Queensland

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  • Shark and ray populations rebounding in Northwestern Atlantic

    Shark and ray populations rebounding in Northwestern Atlantic

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    Newswise — Better fisheries management and conservation is effective at turning the tide on the shark and ray declines, according to a study from Simon Fraser University researchers.

    The fact sharks and rays are increasingly threatened by overfishing has made global headlines in recent years.

    Oceanic populations have plummeted by as much as 71 per cent in the last 50 years and one third of all sharks and rays are threatened with extinction.

    But there is hope, and proof that the declines can be reversed, according to a new study published this week in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).

    Lead author Nathan Pacoureau, postdoctoral research fellow at SFU, and colleagues analyzed trends in fishing pressure, fisheries management, and population status for all wide-ranging coastal sharks and rays that occur in the western Atlantic Ocean.

    They found that populations in the northwest Atlantic recovered following implementation of a U.S. fishery management plan for sharks of the Atlantic Ocean in 1993.

    Declines have been halted in three species and six species of eleven are clearly rebuilding now. This recovery has been achieved by regulation, enforcement, and monitoring.

    A strong system of regulations has been put in place for these species, including catch reporting requirements, aggregate- and species-specific quotas, and catch prohibitions for some species.

    Management is strongly enforced by US Coast Guard and law enforcement agencies, and the government continues to monitor and assess fisheries with additional regulations when needed.

    “Our findings provide hope, but are a microcosm of the wider problem faced by sharks and rays,” says Pacoureau. “Many shark and ray species range widely and successful conservation in one country can be undone by less regulated fishing areas outside those borders.”

    Using the International Union for Conservation of Nature (IUCN) Red List Index, the team showed how populations of the same species had collapsed in the southwest Atlantic due to unrestrained fishing.

    The current number of wide-ranging coastal species threatened with extinction is almost four times lower in the northwest than that in the southwest Atlantic.

    “These sensitive species have very slow life histories and are often collateral damage of sustainable target fisheries for more productive species,” says SFU professor Nick Dulvy, Canada Research Chair in Marine Biodiversity and Conservation.

    The findings highlight the need for well-enforced governance and science-based effective limits on fishing to prevent population collapses and to reduce extinction risk for many species.

    The international study also included researchers from National Marine Fisheries Service in the U.S., James Cook University in Australia and Federal University of Ceará in Brazil.

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    Simon Fraser University

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  • Reduced krill lead to fewer pregnancies in humpback whales

    Reduced krill lead to fewer pregnancies in humpback whales

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    New collaborative research led by scientists at the University of California, Santa Cruz, shows reduced krill supplies lead to fewer pregnancies in humpback whales—a finding that could have major implications for industrial krill fishing.

    The study, published January 15 in Global Change Biology, is based on eight years of data on humpback whale pregnancies (2013 to 2020) in waters along the Western Antarctic Peninsula, where krill fishing is concentrated.

    Krill availability in the year before a humpback pregnancy is crucial because females need to increase their energy stores to support the upcoming pregnancy. In 2017, after a year in which krill were abundant, 86% of the humpback females sampled were pregnant. But in 2020, following a year in which krill were less plentiful, only 29% of humpback females were pregnant.

    Lead author Logan Pallin, a postdoctoral researcher in the Ocean Sciences Department at UC Santa Cruz, said the study demonstrates for the first time the link between population growth and krill availability in Antarctic whales.

    “This is significant because until now, it was thought that krill were essentially an unlimited food source for whales in the Antarctic,” said Pallin, who earned his Ph.D. in ecology and evolutionary biology at UCSC while working on this study. “Continued warming and increased fishing along the Western Antarctic Peninsula, which continue to reduce krill stocks, will likely impact this humpback whale population and other krill predators in the region.”

    “This information is critical as we can now be proactive about managing how, when, and how much krill is taken from the Antarctic Peninsula,” he added. “In years of poor krill recruitment, we should not compound this by removing krill from critical foraging areas for baleen whales.”

    Coauthor Ari Friedlaender, professor of ocean sciences at UC Santa Cruz, said the Western Antarctic Peninsula is experiencing some of the fastest climatic warming of any region on the planet. Winter air temperatures have risen significantly since the 1950s, and the annual sea ice extent is, on average, 80 days shorter than four decades ago.

    “Krill supplies vary depending on the amount of sea ice because juvenile krill feed on algae growing on sea ice and also rely on the ice for shelter,” Friedlaender said. “In years with less sea ice in the winter, fewer juvenile krill survive to the following year. The impacts of climate change and likely the krill fishery are contributing to a decrease in humpback whale reproductive rates in years with less krill available for whales.”

    Coauthor Chris Johnson, the global lead of the World Wide Fund for Nature’s Protecting Whales & Dolphins Initiative, said this research shows that highly precautionary management measures are needed to protect all Antarctic marine life that depends on krill for its survival, including blue, fin, humpback, minke, and southern right whales, as well as other krill predators such as penguins, seabirds, seals, and fish.

    “Krill are not an inexhaustible resource, and there is a growing overlap between industrial krill fishing and whales feeding at the same time,” Johnson said. “Humpback whales feed in the Antarctic for a handful of months a year to fuel their annual energetic needs for migration that spans thousands of kilometers. We need to tread carefully and protect this unique part of the world, which will benefit whales across their entire range.”

    Pallin and Friedlaender collaborated on this research with coauthors from multiple national and international universities, NGOs, non-profits, and government agencies. This work was supported in part by the National Science Foundation, National Geographic Society, and Marine Mammal Commission.

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    University of California, Santa Cruz

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  • Fathoming the hidden heatwaves that threaten coral reefs

    Fathoming the hidden heatwaves that threaten coral reefs

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    Newswise —   In April to May 2019, the coral reefs near the French Polynesian island of Moorea in the central South Pacific Ocean suffered severe and prolonged thermal bleaching. The catastrophe occurred despite the absence of El Niño conditions that year, intriguing ocean scientists around the world.

        An international research team led by Prof. Alex WYATT of the Department of Ocean Science at The Hong Kong University of Science and Technology, has investigated this surprising and paradoxical coral bleaching episode. The unexpected event was related to the passage of anti-cyclonic eddies that elevated sea levels and concentrated hot water over the reef, leading to an underwater marine heatwave that was largely hidden from view at the surface. The findings have recently been published in Nature Communications.  

        Most studies of coral bleaching patterns rely on sea-surface measures of water temperatures, which cannot capture the full picture of threats from ocean heating to marine ecosystems, including tropical coral reefs. These surface measurements conducted over broad areas with satellites are valuable, yet are unable to detect heating below the surface that influences communities living in waters deeper that the shallowest few metres of the ocean.

        Prof. Wyatt and colleagues analyzed data collected at Moorea over 15 years from 2005 to 2019, taking advantage of a rare combination of remotely sensed sea-surface temperatures and high-resolution, long-term in-situ temperatures and sea level anomalies. Results showed that the passage of anti-cyclonic eddies in the open ocean past the island raised sea levels and pushed internal waves down into deeper water. Internal waves travel along the interface between the warm surface layer of the ocean and cooler layers below, and, in a previous study also led by Prof. Wyatt, have been shown to provide frequent cooling of coral reef habitats. The present research shows that, as a result of the anti-cyclones, internal wave cooling was shut down in early 2019, as well as during some earlier heatwaves.  This led to unexpected heating over the reef, which in turn caused large-scale coral bleaching and subsequent mortality. Unfortunately for local reef biodiversity, the extensive coral death in 2019 has offset the recovery of coral communities that had been occurring around Moorea for the last decade.

        A notable observation, in contrast to the 2019 heatwave, was that the reefs in Moorea did not undergo significant bleaching mortality in 2016, despite the prevailing super El Niño that brought warm conditions and decimated many shallow reefs worldwide. The new research demonstrates the importance of collecting temperature data across the range of depths that coral reefs occupy because the capacity to predict coral bleaching can be lost with a focus only on surface conditions. Sea-surface temperature data would predict moderate bleaching in both 2016 and 2019 at Moorea. However, direct observations showed that there was only ecologically insignificant bleaching in 2016, with heating that was short in duration and restricted to shallow depths. The severe and prolonged marine heatwave in 2019 would have been overlooked if researchers only had access to sea-surface temperature data, and the resulting catastrophic coral bleaching may have been incorrectly ascribed to causes other than heating.

        “The present study highlights the need to consider environmental dynamics across depths relevant to threatened ecosystems, including those due to the passage of underwater ocean weather events.  This kind of analysis depends on long-term, in situ data measured across ocean depths, but such data is generally lacking,” Prof. Wyatt said.  

        “Our paper provides a valuable mechanistic example for assessing the future of coastal ecosystems in the context of changing ocean dynamics and climates.”

        This HKUST-led research was conducted in collaboration with a team of scientists from Scripps Institution of Oceanography at the University of California San Diego, the University of California Santa Barbara, California State University, Northbridge, and Florida State University. The data underlying this study were made possible by coupled long-term physical and ecological observations conducted at the Moorea Coral Reef Long-Term Ecological Research (LTER) site. The long-term analyses conducted here, and the concurrent monitoring of physical conditions and biological dynamics across the full range of depths of island and coastal marine communities, is a model for future research that aims to protect vulnerable living resources in the ocean. 

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    Hong Kong University of Science and Technology

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  • Slime for the climate, delivered by brown algae

    Slime for the climate, delivered by brown algae

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    Newswise — Brown algae are true wonder plants when it comes to absorbing carbon dioxide from the air. They even outcompete forests on land in this, and thus play a decisive role for the atmosphere and our climate. But what happens to the carbon dioxide after the algae have absorbed it? Researchers at the Max Planck Institute for Marine Microbiology now report in the Proceedings of the National Academy of Sciences (PNAS) that the brown algae can remove large amounts of carbon dioxide from the global cycle in the long term and thus can counteract global warming.

    Fucoidan: Brown algae slime is not a favourite dish

    Algae take up carbon dioxide from the atmosphere and use the carbon to grow. They release up to a third of the carbon they absorb back into the seawater, for example in the form of sugary excretions. Depending on the structure of these excretions, they are either quickly used by other organisms or sink towards the seafloor.

    “The excretions of brown algae are very complex and therefore incredibly complicated to measure,” says first author Hagen Buck-Wiese from the Max Planck Institute for Marine Microbiology in Bremen. “However, we have managed to develop a method to analyse them in detail.” With this method, the researchers scrutinised a large number of different substances. The so-called fucoidan turned out to be particularly exciting. “Fucoidan made up about half of the excretions of the brown algae species we studied, the so-called bladderwrack,” says Buck-Wiese. Fucoidan is a recalcitrant molecule. “The fucoidan is so complex that it is very hard for other organisms to use it. No one seems to like it.” As a result, the carbon from the fucoidan does not return to the atmosphere quickly. “This makes the brown algae particularly good helpers in removing carbon dioxide from the atmosphere in the long term – for hundreds to thousands of years.”

    Brown algae could bind almost all of Germany’s carbon dioxide emissions

    Brown algae are remarkably productive. It is estimated that they absorb about 1 gigaton (one billion tons) of carbon per year from the air. Using the results of the present study, this would mean that up to 0.15 gigatons of carbon, equivalent to 0.55 gigatons of carbon dioxide, are sequestered by brown algae each year in the long term. For comparison: Germany’s annual greenhouse gas emissions currently amount to about 0.74 gigatons of carbon dioxide, according to the Federal Environment Agency (Umweltbundesamt, estimation for 2020).

    “And even better: The fucoidan does not contain any nutrients such as nitrogen,” Buck-Wiese explains further. Thus, the growth of the brown algae is not affected by the carbon losses.

    More species and sites

    For the current study, Buck-Wiese and his colleagues from the MARUM MPG Bridge Group Marine Glycobiology, which is based at both the Bremen Max Planck Institute and MARUM – Centre for Marine and Environmental Sciences at the University of Bremen, conducted their experiments at the Tvärminne Zoological Station in southern Finland. “Next we want to look into other brown algae species and other locations,” says Buck-Wiese. “The great potential of brown algae for climate protection definitely needs to be further researched and utilised.”

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    Max Planck Institute for Marine Microbiology

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  • Superscattering of water waves – breaking the single channel scattering limit

    Superscattering of water waves – breaking the single channel scattering limit

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    Newswise — Recently, the National Science Review published the study of Huaping Wang’s group at Zhejiang University online. Inspired by electromagnetic metamaterials, the research team designed and fabricated a water wave superscattering device based on degeneracy resonance by using the similarity of water wave equation and electromagnetic wave equation under shallow water conditions, which was realized it experimentally.

    Water waves are a very intuitive fluctuating phenomenon that is widely observed in the natural world. Understanding and controlling the propagation of water waves is significant for both hydrodynamics and marine engineering. In recent years, metamaterials have developed rapidly and become a beneficial tool to manipulate electromagnetic waves, elastic waves, acoustic waves and water waves. Enhanced water wave scattering using metamaterials has a wide range of promising applications in marine energy harvesting and coastal protection.

    Inspired by the superscattering in electromagnetic and acoustic waves, it is possible to design water wave superscatterers based on transformation optics to achieve an increase in the scattering intensity of a given object. However, its experimental implementation remains a great challenge due to the extreme requirements on anisotropic parameters and in water wave conditions.

    Based on the degenerate resonant superscattering mechanism, the researchers theoretically designed and experimentally verified the superscatterer structure of water waves in an experimental water tank. The subwavelength superscatterer is composed of multiple concentric cylinders with different heights, and the geometry and operating frequency of the superscatterer are optimized by a simulated annealing algorithm. By designing resonances with different angular momentum channels, the total scattering cross section can break the limit of single-channel scattering by several times and also far exceed the scattering intensity of ordinary scatterers of the same size. For an ordinary scatterer, the resonances are spread out and the total scattering cross section is limited by the single channel.

    In the experiments, the research group measured the near-field patterns of the water-wave superscatterers, which were in agreement with the theoretical predictions and numerical simulations, and further measured the superscattering effects under different boundary conditions, water depths, and frequencies.

    This study provides a simple and low-cost method to enhance the scattering of water waves, which can be used to enhance the scattering of small sub-wavelength objects, and this is highly relevant for marine engineering, offshore coastal protection, etc., and may be used in marine energy harvesting devices and coastal protection facilities in the future.

    ###

    See the article:

    Superscattering of water waves

    https://doi.org/10.1093/nsr/nwac255

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    Science China Press

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  • Microplastics deposited on the seafloor triple in 20 years

    Microplastics deposited on the seafloor triple in 20 years

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    Newswise — The total amount of microplastics deposited on the bottom of oceans has tripled in the past two decades with a progression that corresponds to the type and volume of consumption of plastic products by society. This is the main conclusion of a study developed by the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) and the Department of the Built Environment of Aalborg University (AAU-BUILD), which provides the first high-resolution reconstruction of microplastic pollution from sediments obtained in the northwestern Mediterranean Sea.

    Despite the seafloor being considered the final sink for microplastics floating on the sea surface, the historical evolution of this pollution source in the sediment compartment, and particularly the sequestration and burial rate of smaller microplastics on the ocean floor, is unknown.

    This new study, published in the journal Environmental Science and Technology (ES&T), shows that microplastics are retained unaltered in marine sediments, and that the microplastic mass sequestered in the seafloor mimics the global plastic production from 1965 to 2016. “Specifically, the results show that, since 2000, the amount of plastic particles deposited on the seafloor has tripled and that, far from decreasing, the accumulation has not stopped growing mimicking the production and global use of these materials,” explains ICTA-UAB researcher Laura Simon-Sánchez.

    Researchers explains that the sediments analysed have remained unaltered on the seafloor since they were deposited decades ago. “This has allowed us to see how, since the 1980s, but especially in the past two decades, the accumulation of polyethylene and polypropylene particles from packaging, bottles and food films has increased, as well as polyester from synthetic fibres in clothing fabrics,” explains Michael Grelaud, ICTA-UAB researcher. The amount of these three types of particles reaches 1.5mg per kilogram of sediment collected, with polypropylene being the most abundant, followed by polyethylene and polyester. Despite awareness campaigns on the need to reduce single-use plastic, data from annual marine sediment records show that we are still far from achieving this. Policies at the global level in this regard could contribute to improving this serious problem.

    Although smaller microplastics are very abundant in the environment, constraints in analytical methods have limited robust evidence on the levels of small microplastics in previous studies targeting marine sediment. In this study they were characterised by applying state-of-the-art imaging to quantify particles down to 11 µm in size.

    The degradation status of the buried particles was investigated, and it was found that, once trapped in the seafloor, they no longer degrade, either due to lack of erosion, oxygen, or light. “The process of fragmentation takes place mostly in the beach sediments, on the sea surface or in the water column. Once deposited, degradation is minimal, so plastics from the 1960s remain on the seabed, leaving the signature of human pollution there,” says Patrizia Ziveri, ICREA professor at ICTA-UAB.

    The investigated sediment core was collected in November 2019, on board the oceanographic vessel Sarmiento de Gamboa, in an expedition that went from Barcelona to the coast of the Ebro Delta, in Tarragona, Spain. The research group selected the western Mediterranean Sea as a study area, in particular the Ebro Delta, because rivers are recognized as hotspots for several pollutants, including microplastics. In addition, the influx of sediment from the Ebro River provides higher sedimentation rates than in the open ocean.

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    Universitat Autonoma de Barcelona

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  • New study highlights urgent need to safeguard deep reefs – one of the largest and least protected ecosystems

    New study highlights urgent need to safeguard deep reefs – one of the largest and least protected ecosystems

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    Newswise — As world leaders, government negotiators, scientists and conservationists gather at the UN Biodiversity Conference, COP15, to agree to halt and reverse nature loss, an international team of marine scientists and conservationists have made an impassioned plea for the urgent conservation of deep reefs.

    Their calls are based on a new study, recently published in the journal Conservation Letters, led by scientists from Nekton, the Western Indian Ocean (WIO) and the University of Oxford. This confirms for the first time that deep reef habitats, notably in the WIO, are largely unprotected despite being under threat from a multitude of stressors, including overfishing, pollution, climate change and, in the near future, seabed mining.

    Their calls follow COP27 in Egypt, where many scientists, politicians and campaigners concluded that the 1.5C climate goal died, signing the death warrant on the vast majority of shallow reefs.

    Deep reefs (found below 30 m) provide essential ecosystem services for climate change resilience, ocean health, and food security whilst also acting as a refugia for organisms threatened in shallow water, including commercially important species. Despite this, deep reefs are barely protected, even though they have a larger geographic footprint than their shallower counterparts. Furthermore, the scarcity of fish in shallow waters combined with modern deep sea fishing technologies is resulting in deep reefs being increasingly exploited by coastal communities who need fish for their food security.

    “We strongly encourage deep reefs to be included in conservation and sustainable management action to complement global targets, notably 30% protection of the global ocean by 2030” said the study’s lead author, Dr Paris Stefanoudis, a marine biologist at the University of Oxford’s Department of Biology and a Research Scientist at Nekton. “Deep reefs are critical to a healthy marine ecosystem and face similar threats from overfishing, pollution and climate change faced by the much-imperilled shallow reef system.”

    Covering over 8% of the global ocean, the Western Indian Ocean is one of the least known, least protected, and most threatened marine regions of our planet. Shallow and deep coral reefs of the WIO are marine biodiversity hotspots with high numbers of species that are found nowhere else on Earth. They are essential to the region’s 100 million people living within 100km of the coastline, including over three million people who are directly dependent on artisanal fishing for their livelihoods. The population is projected to double over the next 30 years, driving greater stressors on the ocean’s biological capacity to support lives and livelihoods.

    The scientific team has co-developed a new framework for conserving deep reefs including practical recommendations and specific actions for regional policy-makers, conservationists and scientists. This has been published in the journal Conservation Letters.

    The researchers urge policy makers to use the COP15 summit to agree to the following:

    1. Highly protect 30% of ecosystems by 2030 (‘30 by 30’), and include deep reefs in this target.
    2. Conserve deep reef ecosystems and their resources by specifically including them in fishery regulations, marine protected areas, and marine spatial planning.
    3. Extend current management efforts on shallow reefs to include deep reefs as these ecosystems are often connected.
    4. Invest in foundational, fundamental, and applied research on deep reef biodiversity, ecosystem functioning and provided services.
    5. Develop national, international, transnational cross-stakeholder collaborations to survey and conserve deep reefs in national and international (High Seas) waters

    “To halt and reverse nature loss, the UN Biodiversity Conference, COP15 must prioritise the conservation of unique ecosystems such as deep reefs, one of the least protected ecosystems on Earth” stated co-author Professor Lucy Woodall, Professor of Marine Biology at the University of Oxford, Nekton Principal Scientist, “We hope our recommendations and actions will be useful for decision makers in the WIO, be applied within the new Western Indian Ocean regional policy and provide the springboard for deep reefs to become protected across the global ocean”, continued Professor Woodall.

    Co-author Melita Samoilys, CORDIO East Africa explains: “Our framework was jointly developed with a range of stakeholders from academia, research, management and government, and provides a list of actions across three themes: capacity, information collection, and information sharing. Given the scale of the issue, we have also identified which parties – such as funding agencies, government, Institutions or the research community – are needed to work together to realise those actions”.

    “To ensure a prosperous and resilient Western Indian Ocean, it is essential that deep reefs are no longer ignored by scientists and policy makers, and they must be specifically considered in conservation and management strategies”, shared co-author Athur Tuda, Executive Director of the Western Indian Ocean Marine Science Association, WIOMSA.

    A video summary of the findings and proposals is available at https://www.youtube.com/watch?v=lz1Tm2wo2JU&t=2s 

     

    Notes for Editors

    The Publication

    ‘Stakeholder-derived recommendations and actions to support deep-reef conservation in the Western Indian Ocean’ published in Conservation Letters, co-authored by 18 scientists representing 18 different organisations including from South Africa, Tanzania, Seychelles, Kenya, Mozambique, UK and USA. https://conbio.onlinelibrary.wiley.com/doi/epdf/10.1111/conl.12924

    Video, photographic and infographic content: https://nektonmission.org/about/press-news

    WIO Conservation Framework: The UNEP’s Nairobi Convention provides the regional framework for governments, civil society and the private sector to strengthen the health and resilience of the Indian Ocean. At the Nairobi Convention’s COP10 in November 2021, the WIO nations unanimously agreed to co-create an ambitious new regional ocean strategy and accompanying policies to support sustainable ocean development underpinned by science-based management. ‘The Western Indian Ocean – Resilience & Prosperity Initiative’ (WIO-RPI), as it’s known includes establishing a just, equitably designed and managed connected network of ecologically and culturally representative protected areas in national and international waters, complementing global targets. Nekton and University of Oxford scientists are the technical partners supporting the implementation of the WIO-RPI.

    Deep Reefs: Deep reefs include mesophotic (30-150 m), rariphotic (150-300 m), and cold-water coral reefs (>300 m) and have a great geographic                              

    Nekton: Nekton works to accelerate the scientific exploration and conservation of the ocean for people and the planet. Nekton is an independent, not-for-profit research institute and is a UK registered charity. www.nektonmission.org

    University of Oxford: Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the seventh year running, and ​number 2 in the QS World Rankings 2022. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer. Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 200 new companies since 1988. Over a third of these companies have been created in the past three years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing £15.7 billion to the UK economy in 2018/19, and supports more than 28,000 full time jobs.

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    University of Oxford

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  • Genetic barriers, a warming ocean, and the uncertain future for an important forage fish

    Genetic barriers, a warming ocean, and the uncertain future for an important forage fish

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    Newswise — In the vast oceans, one would assume their inhabitants can travel far and wide and, as a result, populations of a species would mix freely. But this doesn’t appear to be the case for a vital forage fish called the sand lance.

    Sand lance are small schooling fish impressively rich in lipids, which makes them a fantastic and significant food source for at least 70 different species ranging from whales and sharks to seabirds, says UConn Associate Professor of Marine Sciences Hannes Baumann.

    The Northern sand lance can be found from the waters off New Jersey all the way north to Greenland. Researchers, including Baumann and Ph.D. student Lucas Jones, were interested to see if sand lance constitute a massive, homogenous population, or whether there are genetically distinct groups. Their findings are published in the ICES Journal of Marine Science.

    Baumann explains these are important questions to answer when considering conservation and sustainable management of the species, especially since the regions where sand lance live are warming faster than many areas of the planet due to climate change.

    Sampling fish from such a broad range is no small task, but two years ago, Baumann and Jones began reaching out to other researchers to see if they had tissue samples to spare. Baumann credits the work to the international group of colleagues who contributed samples including co-authors from Canada and Greenland, and who helped sequence and analyze the data including co-authors from Cornell University.

    In all, Baumann, Jones, and the team were able to sequence and analyze nearly 300 samples from a variety of locations across the sand lance’s range using a technique called low-coverage whole genome sequencing. They also sequenced the first reference genome for sand lance.

    In a nutshell, Baumann says they found an area on the Scotian Shelf, off the coast of Nova Scotia, where a genetic break occurs. The researchers distinguished two distinct groups, one north and one south of the divide, with parts of the genome differing quite dramatically – namely on chromosomes 21 and 24. Without obvious physical barriers like a mountain range separating the groups, Baumann says it’s logical to ask how these differences are possible.

    “That is the scientific conundrum,” says Baumann, and the answer, it appears, lies in the currents.

    “When fish from the north reproduce and drift south, they are genetically less adapted to warmer southern waters, even if it’s five or six degrees warmer in the winter, they are just not surviving,” Baumann says. “These populations may be linked by the ocean currents, but the realized connectivity is basically zero.”

    This finding is a first for the sand lance, but it has been shown in other species such as lobsters, cod, and scallops, and this research adds further evidence to an apparent temperature divide at the Scotian Shelf, and helps demonstrate that temperature is an important factor in survival.

    “Example after example shows that the ocean is not as homogeneous a place as expected, and there are all kinds of things that prevent that constant mixing,”Baumann says. “We found another striking example of that.”

    When researchers find adaptation in an environment where mixing is continuous, like in the ocean, Baumann says, the question is how it is possible that groups stay different, even though they are constantly encountering other genotypes. That is where powerful genomic methods, like the ones used in this paper, come in handy.

    “Parts of the genome in many species have what we call a ‘genetic inversion,’ which means that the genes on the chromosome from one parent have a certain order and the genes on the same chromosome that come from the other parent that code for the same thing, and they’re the same area, but they’re flipped,” Baumann says.

    These inversions mean recombination cannot occur; therefore, the genes are passed down through the generations and play an important role in adaptation.

    “We discovered on chromosomes 21 and 24 there are whole regions that are completely different and that is like the trademark signature of what we call an inversion because there’s no recombination going on.”

    Baumann says that knowing there are genetic and ecological barriers on the Scotian Shelf is important, because with climate change, this barrier may move north and while that may be good news for southern fish, it’s bad news for the fish currently there.

    The researchers were also a little relieved in finding two clusters, because had there been many smaller clusters, it could make management and conservation more challenging, especially considering scenarios like the construction of offshore wind parks. Areas potentially well situated for wind turbines can also be habitats for sand lance, and construction disrupts habitats. If there were many, smaller population clusters, a single construction project could pose the risk of completely wiping out a cluster, whereas with more widely dispersed populations, though the local population may be temporarily disturbed, it will not be long before they are able to re-establish after construction is completed.

    Baumann plans to focus further research on studying the genetic basis of the thermal divide.

    “We want to make sure that this fish is productive and resilient, despite climate change, so we should make sure these areas where they are occurring are protected,” Bauman says. “These decisions should include experts to ensure if there’s an area that is very critical to sand lance, that any disturbance is temporary.”

    It isn’t an unsolvable conflict, but it is something that we need to do, says Baumann, who also notes that it is possible that sand lance north of the thermal divide are already suffering more from warming because the region is warming faster.

    “It could be that these two clusters have different vulnerabilities to climate change,” he says. “We don’t know that yet but that’s something that should be pursued.”

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    University of Connecticut

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  • To save nature, focus on populations, not species

    To save nature, focus on populations, not species

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    Newswise — AMHERST, Mass. – Human-released greenhouse gasses are causing the world to warm, and with that warming comes increasing stress for many of the planet’s plants and animals. That stress is so great that many scientists believe we are currently in the midst of the “sixth extinction,” when entire species are disappearing up to 10,000 times faster than before the industrial era. However, scientists have been uncertain which ecosystems, and which species, are most at risk. New research, recently published in Nature Climate Change, is the first to show that the focus on species-level risk obscures a wide variability in temperature tolerance, even within the same species, and that this variability is greater for marine species than terrestrial ones. The findings have immediate implications for management and conservation practices and offer a window of hope in the effort to adapt to a rapidly warming world.

    “One of the most important biological discoveries in the last century is that evolution can happen much more quickly than previously thought,” says Brian Cheng, professor of marine ecology at the University of Massachusetts Amherst and the paper’s senior author. “One of the implications of this is that different populations of the exact same species can adapt to their local environments more readily than traditional biology would have thought possible.”

    It turns out that this rapid, localized adaptation may be able to help ensure survival in a warming world.

    By conducting a metanalysis of 90 previously published studies, from which Cheng and his co-authors mined data on 61 species, the team was able to construct a set of “upper thermal limits”—specific temperatures above which each species could not survive. However, by zooming in further and looking at 305 distinct populations drawn from that pool of 61 species, they found that different populations of the same marine species often had widely different thermal limits. This suggests that some populations have evolved different abilities to tolerate high temperatures. The key then, is to keep different populations of the same species connected so that the populations that have adapted to the higher temperatures can pass this advantage on to the populations with the lower thermal limits.

    In other words, imagine a wide-ranging marine species, such as the diminutive Atlantic killifish, which occurs from the warm Florida coast of the United States north to the frigid waters of Newfoundland, Canada. The northern killifish populations may be better able to withstand warming waters if some of their southern kin are able to naturally shift their range to the north.

    “Scale matters,” says Matthew Sasaki, a marine biologist and evolutionary ecologist who completed this research as part of his postdoctoral fellowship at the University of Connecticut and is the paper’s lead author. “The patterns you see across species aren’t the same you see within species, and the big-picture story doesn’t necessarily match what is happening on the local level.”

    In yet another twist, the team, which was funded by the National Science Foundation and was composed of biologists specializing in terrestrial as well as marine ecosystems, discovered that this intra-species variability was primarily a feature of animals living in the ocean and intertidal areas. Populations of widespread species that live on land or in freshwater exhibit far more homogeneity in their thermal limits, and thus could be more sensitive to rising temperatures. However, on land, plants and animals can take advantage of microclimates to cool down and avoid extreme temperatures, by moving into shady spots, for example.

    Taken together, the research suggests that a one-size-fits-all-species approach to conservation and management won’t work. Instead, write the authors, we need to understand how populations have adapted to their local conditions if we want to predict their vulnerability to changing conditions. A more effective approach would include ensuring that marine species can find wide swaths of undamaged habitat throughout their entire range, so that different populations of the same species can mix and pass on the adaptations that help them survive warmer waters. And on land, we need to maintain large patches of cool ecosystems—such as old-growth forests—that terrestrial species can use as refuges.

    “The glimmer of hope here,” says Cheng, “is that with conservation policies tailored to individual populations, we can buy them time to adapt to the warming world.”

     

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  • As temps rise, low marsh emits more carbon gas than high marsh

    As temps rise, low marsh emits more carbon gas than high marsh

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    Newswise — WOODS HOLE, Mass. — Salt marshes are a well-known carbon sink and can aid in carbon sequestration efforts. But they are also dynamic ecosystems that change with the seasons and tides.

    New research out of the Marine Biological Laboratory (MBL) Ecosystems Center shows how seasonal cycles and the ocean’s ebb and flow affect the amount of carbon stored in New England marshes, using Sage Lot Pond on Cape Cod as a reference marsh.

    “In our recent study, we asked: How does marsh respiration (the conversion of organic carbon to carbon dioxide) vary as a function of temperature, both of air and sediment? This can help us understand how climate change, particularly warming, alters respiration rates in a marsh,” said Joanna Carey, associate professor of environmental science at Babson College. Carey conducted this research while an MBL postdoctoral scientist with Jianwu (Jim) Tang, MBL senior scientist, and Kevin Kroeger, supervisory research chemist with the U.S. Geological Survey.

    Carey and her collaborators looked at gas exchange from the Sage Lot Pond marsh system over 16 months between 2014 and 2016. They installed static gas chambers in six plots, from high elevation marsh (which is flooded only a few days a month with the tides) to low elevation marsh (which is flooded twice daily with tides). The chambers recorded amount of carbon dioxide released to the atmosphere each second for four minutes straight. The large date range and varied elevations allowed them to capture data representing a spectrum of seasonal temperatures experienced by the marsh.

    Upon reviewing the data, they saw that each degree of warming correlated with an exponential increase in carbon dioxide emission.

    “But what was surprising is that we found higher temperature sensitivity in the low marsh habitat. That means for each degree of warming, there was significantly more carbon dioxide released from the marsh at lower elevation relative to the high-marsh habitat,” Carey said.

    Low marshes store more carbon, which had seemed like a good thing for natural carbon sequestration—especially since sea-level rise is resulting in the conversion of high-marsh to low marsh environments. But this research shows that as the world warms, the sequestration benefit from low marshes may be diminished, since carbon dioxide is released there at a much higher rate with increasing temperatures.

    Sage Lot Pond is a well-quantified marsh, with a number of studies detailing various aspects of carbon movement. The study also showed that this Sage Lot marsh environment loses much more respired carbon to the ocean via ebbing tides than it does directly via vertical fluxes to the air. This is important because, although some of the respired carbon will be returned to the atmosphere as a carbon dioxide flux from the sea, a portion likely remains dissolved in the ocean for extended time, perhaps thousands of years, thereby enhancing the carbon sequestration value of salt marshes.

    Carey and her collaborators hope to continue in this line of work by studying nitrogen loads and emissions using similar techniques. They also want to see how their findings might extend to other marshes. Tracking the fate of carbon and other gases in marshland gives a fuller picture that can inform policies to address climate change and help us understand the fate of these valuable ecosystems. 

    ####

    The Marine Biological Laboratory (MBL) is dedicated to scientific discovery – exploring fundamental biology, understanding marine biodiversity and the environment, and informing the human condition through research and education. Founded in Woods Hole, Massachusetts in 1888, the MBL is a private, nonprofit institution and an affiliate of the University of Chicago.

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  • Microphytobenthos in the Dutch Wadden Sea feeds on ‘left-overs’ in the bottom

    Microphytobenthos in the Dutch Wadden Sea feeds on ‘left-overs’ in the bottom

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    Isotopes
    Newswise — For the study, Riekenberg and colleagues looked at the chemical variations in the isotopes of nitrogen. There are two predominate forms of nitrogen, ‘nitrogen-14’ and the heavier version, ‘nitrogen-15’. When an organism digests protein, for example from plankton, the resulting nitrogen is used to create its own proteins. In this process, the lighter nitrogen-14 is lost a bit, so the relative concentration of the heavy nitrogen increases a little at each step in the food chain. As a result, animals higher up the food chain retain relatively more and more nitrogen-15.

    Individual amino acids
    In recent years, it has become possible to also analyze the different nitrogen isotopes from individual amino acids. Certain amino acids (the building blocks of protein) cannot be created by higher organisms themselves. As a result, those essential or ‘source amino acids’ need to be obtained from the diet and remain mostly unchanged throughout the food chain. Therefore, in these amino acids, the stable isotope ratio of nitrogen does not become progressively higher with each step of eating or being eaten. Other, so-called trophic amino acids do change a lot during metabolism through each step of the food chain. Thus, the difference in nitrogen composition between trophic and essential amino acids provides a measure of how high up the food chain an organism is, independent of any variations in underlying nitrogen sources supporting the ecosystem. We used this technique to build a trophic structure from direct measurements of the Dutch Wadden Sea food web.   

    Detritus in the pore water
    Using samples that were collected between 2011 and 2014 during the long-lasting monitoring program of NIOZ, SIBES (the Synoptic Intertidal BEnthic Survey), Riekenberg analyzed the nitrogen isotopes of amino acids from 340 different animals from across the Dutch Wadden Sea. Thus, he was able to trace back the sources of nitrogen that these animals used. Riekenberg: “We saw that quite a bit of the nitrogen did not come from the overlying water column, but from the benthic primary producers, like diatoms, using nitrogen from the pore water at the bottom of the Wadden Sea. This nitrogen has a distinct signal, since it is what remains after the breaking down of organic matter and denitrification, and can therefore be tracked into a portion of the food web.”

    Ecological models
    Riekenberg stresses that this new piece of the jigsaw adds important knowledge to the science of the Wadden Sea ecosystem. “Now that we know that detrital nitrogen in porewaters is an important direct source of nutrients, this should be included in ecological models we make of the Wadden Sea. If our models do not include all pools of nutrients supporting the food web, then how can these models accurately reflect the ecology of the Wadden Sea when they are used to predict future impacts or changes?”

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    Royal Netherlands Institute for Sea Research

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  • Synthetic fibers discovered in Antarctic air, seawater, sediment and sea ice as the ‘pristine’ continent becomes a sink for plastic pollution

    Synthetic fibers discovered in Antarctic air, seawater, sediment and sea ice as the ‘pristine’ continent becomes a sink for plastic pollution

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    Newswise — As nations meet in Uruguay to negotiate a new Global Plastics Treaty, marine and forensic scientists publish new results this week that reveal the discovery of synthetic plastic fibres in air, seawater, sediment and sea ice sampled in the Antarctic Weddell Sea. The field research was undertaken during an expedition to discover Sir Ernest Shackleton’s ship, the Endurance. The results are published in the journal Frontiers in Marine Science.

    Fibrous polyesters, primarily from textiles, were found in all samples. The majority of microplastic fibres identified were found in the Antarctic air samples, revealing that Antarctic animals and seabirds could be breathing them.

    ‘The issue of microplastic fibres is also an airborne problem reaching even the last remaining pristine environments on our planet’, stated co-author Professor Lucy Woodall, University of Oxford, Nekton Principal Scientist. ‘Synthetic fibres are the most prevalent form of microplastic pollution globally and tackling this issue must be at the heart of the Plastic Treaty negotiations.’ Professor Woodall was the first to reveal the prevalence of plastic in the deep sea in 2014.

    A modelling analysis of air trajectories revealed that areas with higher numbers of fibres were associated with winds coming from southern South America. The discovery reveals that the Antarctic Circumpolar Current and the associated polar front is not, as previously thought, acting as an impenetrable barrier which would have prevented microplastics from entering the Antarctic region.

    ‘Ocean currents and winds are the vectors for plastic pollution to travel across the globe and even to the remotest corners of the world’, shared Nuria Rico Seijo, Nekton Research Scientist, Oxford, the co-lead author of the research. ‘The transboundary nature of microplastics pollution provides more evidence for the urgency and importance of a strong international plastic pollution treaty.’

    The concentration of microplastics was also discovered by the team to be far higher in sea ice than in other sample types. Research indicates that microplastics are being trapped during the creation of the sea-ice layer every year.

    ‘Sea ice is mobile, can travel vast distances and reach the permanent ice shelves of the Antarctica continent where it can be trapped indefinitely with its gathered microplastic pollutants’, shared Dr Mánus Cunningham, Nekton Research Scientist, Oxford, the co-lead author of the research. ‘We believe the acquisition of microplastics in the multi-year sea ice combined with its seasonal changes could also be considered a temporary sink and one of the main transporters of microplastics within the Antarctic region’, concluded Dr Cunningham.

    Extensive research was also conducted on sediment samples retrieved at depths ranging from 323 to 530 metres below the sea’s surface during the Weddell Sea Expedition. ‘Our discovery of microplastics in seabed sediment samples has revealed evidence of a plastic sink in the depths of the Antarctic waters’, said Professor Woodall. ‘Yet again we have seen that plastic pollution is being transported great distances by wind, ice and sea currents. The results of our research collectively demonstrate the vital importance of reducing plastic pollution globally.’

    The scientific and forensic experts at Nekton’s Oxford University and collaborating laboratories (Staffordshire University, University of Cape Town and Nelson Mandela University) used a range of investigative methods to analyse the samples in the study. These include optical (Polarised Light Microscopy), chemical (Raman Spectrometry) investigative technologies and even a specialist adhesive “crime scene” tape to identify the polymer type. The modelling analysis used a method called Air Mass Back Trajectory analysis.

    ‘Our use of forensic science approaches had two important benefits; improved methods for both the reduction and monitoring of possible procedural contamination in the samples, and also more detailed characterisation of the microplastics, beyond just polymer type, allowing for better understanding of the number of possible sources. We would encourage future studies to harness these forensic approaches to ensure more robust data is gathered’ said Professor Claire Gwinnett, Staffordshire University.

    According to the research team, the findings add urgency for a binding, globally agreed treaty to prevent microplastics from entering the environment, particularly oceans. Ahead of the Global Plastic Treaty discussions, they call on policy makers to:

    • Reduce plastic pollution and production globally, by creating a robust global plastics treaty that builds on national and regional initiatives;
    • Align plastic reduction actions with natural and societal targets to achieve multiple positive outcomes for society;
    • Empower local communities to co-develop and use programmes that support full life-cycle solutions to plastic waste management.

    They add that concerned individuals can also play their part by adopting simple lifestyle habits to reduce synthetic microfibre pollution. These include:

    1. Fill your washing machine: more space to move around in the wash results in microfibres falling off.
    2. Wash at 30C: gentle cycles and lower temperatures decreases microfibre shedding.
    3. Ditch the dryer: tumble dryers generate about 40 times more microfibers than washing machines.
    4. Microfibre capture for washing machines, e.g. GuppyFriend (https://guppyfriend.com) or Coraball (https://www.coraball.com).
    5. Choose natural fibres, e.g. organic natural fibres like cotton, linen, hemp.
    6. Avoid microfibre cleaning cloths – use natural alternatives.
    7. Wash textiles less!

    Source: A Sustainable Life: https://www.asustainablelife.co.uk/7-easy-ways-to-reduce-microfibre-pollution/

    Notes for Editors

    The Publication: ‘The transport and fate of microplastic fibres in the Antarctic: The role of multiple global processes’ published in Frontiers in Marine Science. https://www.frontiersin.org/articles/10.3389/fmars.2022.1056081/full

    Research Partners: The international team, led by Nekton and scientists from Department of Biology, University of Oxford, collaborating with experts from UK and South African research institutions including Staffordshire University (UK), Nelson Mandela University, and the University of Cape Town (South Africa).

    Video, photographic and infographic content: https://nektonmission.org/about/press-news                                           

    Nekton: Nekton works to accelerate the scientific exploration and conservation of the ocean for people and the planet. Nekton is an independent, not-for-profit research institute and is a UK registered charity. www.nektonmission.org

    University of Oxford: Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the seventh year running, and ​number 2 in the QS World Rankings 2022. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer. Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 200 new companies since 1988. Over a third of these companies have been created in the past three years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing £15.7 billion to the UK economy in 2018/19, and supports more than 28,000 full time jobs.

    Flotilla Foundation: The research was funded by a philanthropic grant from the Flotilla Foundation, a Netherlands based charity that aims to pro­mote the con­ser­va­tion, pro­tec­tion and improve­ment of the phys­i­cal and nat­ur­al envi­ron­ment, in par­tic­u­lar­ly the ocean.

    Weddell Sea Expedition: Led by the Flotilla Foundation and in partnership with Nekton, Scott Polar Research Institute, Nelson Mandela University, University of Cape Town and the University of Canterbury – The Weddell Sea Expedition deployed AUVs and ROVs to investigate life beneath the ice and the potential implications of climate change. 36 scientists, surveyors and technicians participated in the 45-day voyage in December 2019 to January 2020. Whilst in the Weddell Sea, the Expedition sought to locate Sir Ernest Shackleton’s vessel The Endurance. The expedition paved the way for the successful discovery of the vessel in 2022.

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    University of Oxford

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  • What Darwin would discover today

    What Darwin would discover today

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    Newswise — “If Charles Darwin had had the opportunity to dive off the Cape Verde Islands, he would have been completely thrilled”, Eduardo Sampaio is convinced, because Darwin would have seen a fascinating, species-rich landscape. But he lacked the diving equipment. Thus, in his notes The Voyage of the Beagle, Darwin described Cape Verde as a barren landscape.

    Eduardo Sampaio, affiliate member of the Cluster of Excellence “Centre for the Advanced Study of Collective Behaviour” (CASCB) at the University of Konstanz, had quite the opposite experience. He was invited on board the ship Captain Darwin by filmmaker Victor Rault to continue his octopus research.

    Victor Rault, 30, set sail from Plymouth on the Captain Darwin in 2021, following in the footsteps of Darwin’s HMS Beagle. He wants to explore how the ecosystem has changed since Darwin’s voyage on the HMS Beagle in 1832. Researchers and citizens have been invited to travel along and conduct experiments in the spirit of Darwin. “When Victor told me about his project, I was baffled”, recalls biologist Eduardo Sampaio from Portugal. He says: “It was immediately clear to me that it’s an excellent idea to retrace the path of Charles Darwin. I was more than keen to jump on board!”

    What do octopuses see in a mirror image?
    Eduardo Sampaio spent ten days on the Captain Darwin. The focus was on the dives: The biologist, who works with the Max Planck Institute of Animal Behavior, actually wanted to observe the joint hunting behaviour of octopuses and fish. However, as it was mating season, the animals rarely showed themselves. If they came out, they wanted to interact with other octopuses and did not hunt at all.

    So, he spontaneously changed his research project and conducted a mirror test instead: “We wanted to determine whether the octopuses could realize that they were seeing another individual in the mirror.” In the evening on board, the crew watched the video footage: “When the octopus approached the mirror, it changed colour – but only the side facing the mirror changed. That was very fascinating to watch”, says Eduardo Sampaio. In a further experiment, the researcher now wants to test whether the octopuses can even recognize themselves.

    Bringing Darwin’s research style up to date
    In the evenings, Eduardo Sampaio read Darwin’s The Origin of Species, because “it inspired me”. Often, he wondered: “How can we update Darwin’s kind of scientific work with the new methods we have today, like machine learning and computer vision, to better understand how animals move in their natural habitats or use different strategies to exploit social information?” He does not have an answer yet, but may find it the next time he sails on the Captain Darwin.

    Great support for scientists who do not have the necessary resources
    Eduardo Sampaio will be back on board the Captain Darwin: “This trip, launched as a Citizen Science project, is a great support for researchers who don’t have the means to do this kind of field research, especially for researchers from disadvantaged areas and in countries where research structures are not so well equipped.” Much of the work that researchers usually have to handle themselves was taken over, such as obtaining permits, purchasing equipment and raising funds. “I also realized that citizens can play a much more active role in science than just collecting data”, says Eduardo Sampaio, who hopes that this sailing trip will be a prelude to more exciting Citizen Science expeditions. Eduardo Sampaio and Victor Rault also wrote a report about the collaboration published in PLOS Biology on 15 November 2022.

    Key facts

    • Dr Eduardo Sampaio from the Cluster of Excellence “Centre for the Advanced Study of Collective Behaviour” and researcher at the Max Planck Institute of Animal Behavior participated in a Citizen Science-led expedition
    • Publication on the benefits of such research projects in PLOS Biology: Sampaio E, Rault V (2022) Citizen-led expeditions can generate scientific knowledge and prospects for researchers. PLoS Biol 20(11):e3001872. https://doi.org/10.1371/journal.pbio.3001872

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    University of Konstanz

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  • FSU researchers: Rapid fluctuations in oxygen levels coincided with Earth’s first mass extinction

    FSU researchers: Rapid fluctuations in oxygen levels coincided with Earth’s first mass extinction

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    Newswise — Rapid changes in marine oxygen levels may have played a significant role in driving Earth’s first mass extinction, according to a new study led by Florida State University researchers.

    About 443 million years ago, life on Earth was undergoing the Late Ordovician mass extinction, or LOME, which eliminated about 85% of marine species. Scientists have long studied this mass extinction and continue to investigate its possible causes, such as reduced habitat loss in a rapidly cooling world or persistent low-oxygen conditions in the oceans.

    By measuring isotopes of the element thallium — which shows special sensitivity to changes in oxygen in the ancient marine environment — the research team found that previously documented patterns of this mass extinction coincided with an initial rapid decrease in marine oxygen levels followed by a rapid increase in oxygen. Their work is published online in the journal Science Advances.

    “Paleontologists have noted that there were several groups of organisms, such as graptolites and brachiopods, that started to decline very early in this mass extinction interval, but we didn’t really have any good evidence of an environmental or climate signature to tie that early decline of these groups to a particular mechanism,” said co-author Seth Young, an associate professor in the Department of Earth, Ocean and Atmospheric Science. “This paper can directly link that early phase of extinction to changes in oxygen. We see a marked change in thallium isotopes at the same time these organisms start their steady decline into the main phase of the mass extinction event.”

    That decrease in oxygen was immediately followed by an increase. This rapid shift in oxygen coincided with the traditional first die-off of mass extinction and major ice sheet growth over the ancient South Pole.

    “Turbulence in oxygen levels in oceanic waters is really what seems to have been pretty problematic for organisms that were living in the Late Ordovician at that time, which might have been adapted to cope with low oxygen conditions initially or vice versa,” Young said. “The fact that oxygen levels in the oceans next to the continents switching back and forth over short geologic time scales (a few hundred thousand years) really did seem to play havoc with these marine ecosystems.”

    The Late Ordovician extinction was one of five major mass extinctions in Earth’s history and the only one scientists are confident took place in what are called “icehouse” conditions, in which widespread ice sheets are present on Earth’s surface. Earth is currently experiencing icehouse conditions and loss of biodiversity, which makes this ancient mass extinction an important analog for present-day conditions, along with trying to understand Earth’s future as our climate continues to warm and ice sheets recede.

    Previous research into environmental conditions surrounding the LOME used evidence found in limestones from more oxygenated settings, but this study used shales that were deposited in deeper, oxygen-poor water, which record different geochemical signatures, allowing the researchers to make conclusions about global marine conditions, rather than for local conditions.

    “The discovery of the initial expansion of low-oxygen conditions on a global level and the coincidence with the early phases of decline in marine animals helps paint a clearer picture of what was happening with this extinction event,” said lead author Nevin Kozik, a visiting assistant professor at Occidental College and former FSU doctoral student.

    Co-authors on this paper were doctoral student Sean Newby and associate professor Jeremy Owens of FSU; former FSU postdoctoral scholar and current assistant professor at the College of Charleston Theodore Them; Mu Liu and Daizhao Chen of the Chinese Academy of Sciences; Emma Hammarlund of Lund University; and David Bond of the University of Hull.

    This research was supported by the National Science Foundation, the American Chemical Society, the Sloan Research Foundation and the Geological Society of America.

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  • Surf’s up (and don’t mind the sharks)

    Surf’s up (and don’t mind the sharks)

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    Newswise — Clean, choppy, or cranking, when the surf’s up, so too are the surfers. But even the most avid surfer would steer clear of the waves when a shark is about… or would they? 

    In a new study from the University of South Australia, researchers found that 60 per cent of surfers are not afraid of sharks when surfing, despite more than half of them spotting a shark when out in the water. 

    It’s an interesting finding, particularly given people’s general fascination and fear of sharks, but as behavioural scientist and conservation psychology researcher, UniSA’s Dr Brianna Le Busque, says it’s a step in the right direction when it comes to shark conservation.

    “People have long feared sharks – not surprisingly given the hype generated from modern shark movies,” Dr Le Busque says. 

    “But exaggerated depictions of sharks have unfairly influenced people and as a result, have damaged shark conservation efforts. 

    “Surfers are frequent ocean users, so they’re in a unique position to change these perceptions.

    “Anecdotally, we know that surfers understand the role sharks play in ocean health and, for the most part, believe that shark conservation is good.

    “But the relationship between surfers and sharks is complex and has not been widely researched, so understanding their interactions is an important step in shark conservation and management policies.” 

    Surveying 391 surfers across 24 different countries (predominantly USA), the study found that:

    • 60 per cent were not afraid of sharks when surfing
    • 52 per cent had seen a shark when surfing
    • 44 per cent said a shark sighting would not stop them from going in the water
    • 17 per cent had been bitten or personally knew someone who had been bitten by a shark.

    Globally, 100 million sharks are killed each year with a quarter of shark species threatened by extinction.

    Le Busque says that the study will help to change people’s negative perceptions of sharks.

    “Surfers encounter sharks more than any other people in the community; they should be part of the consultation process when it comes to management or mitigation strategies,” Le Busque says.

    “When we step into the ocean, we step into their environment. We all need to be appropriately informed to ensure a logical balance between safety and conservation.”

    Notes to editors:

    …………………………………………………………………………………………………………………………

     

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  • Food Security Harmed by Warming Ocean, Accelerating Fish Development

    Food Security Harmed by Warming Ocean, Accelerating Fish Development

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    Newswise — (San Diego) October 29, 2022— Higher temperatures spurred by worsening climate change increased the growth rate of fish and consumption of their yolk sac—a structure that provides an embryo with food and helps develop important structures, such as blood cells. In addition, higher temperatures boosted fish mortality rates and led to faster depletion of their yolk sac, according to researchers at Scripps Institution of Oceanography at the University of California San Diego. The findings will be presented this week at the American Physiological Society (APS) Intersociety Meeting in Comparative Physiology: From Organism to Omics in an Uncertain World conference in San Diego. 

    Ocean temperatures are predicted to rise as carbon monoxide gas accumulates due to climate change. To determine the impact on larval white seabass, researchers sampled fish reared at 18–23 degrees Celsius throughout development from birth to six days old. With this process, they were hoping to differentiate the effects of temperature and time. They estimated growth and development rates by examining images obtained under a light microscope, among other methods.

    These findings are important because it helps inform fish population predictions in the face of climate change. The fishing industry is an important link in the U.S. food supply chain. Predicting growth rates and population structures of white seabass, a commercially and recreationally significant population in California, is critically important to help ensure food security.

    “Our results suggest that larval fish recruitment could swing to either extremity as a result of ocean warming,” said Ria Bhabu, co-author of the study and a student at the University of California San Diego. 

    Physiology is a broad area of scientific inquiry that focuses on how molecules, cells, tissues and organs function in health and disease. The American Physiological Society connects a global, multidisciplinary community of more than 10,000 biomedical scientists and educators as part of its mission to advance scientific discovery, understand life and improve health. The Society drives collaboration and spotlights scientific discoveries through its 16 scholarly journals and programming that support researchers and educators in their work. 

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  • Climate Change Negatively Affecting School Sharks

    Climate Change Negatively Affecting School Sharks

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    Newswise — (San Diego) October 29, 2022— Preliminary research data suggest warmer temperatures and increased salt levels might have negative effects on the behavior and physiology of school sharks. A clear indicator of physiological changes is higher levels of stress markers such as glucose and lactate concentrations in the blood. Researchers also noted behavior changes according to the warmer and saltier the environment is and the more time school sharks spend resting. School sharks are usually constantly swimming. A break in their usual activity means they might be too stressed to find food or escape predators. The findings will be presented this week at the American Physiological Society (APS) Intersociety Meeting in Comparative Physiology: From Organism to Omics in an Uncertain World conference in San Diego. 

    Researchers also examined the response of school sharks to increases in temperatures and salinity levels based on neonatal and juvenile (one year old and older) stage. The findings show newborns were more tolerant of some of the environmental changes than juveniles. This suggests neonates might have a special ability at birth to inhabit coastal waterways where freshwater mixes with salt water before migrating into deeper waters as juveniles. 

    The shallow water home of school sharks is constantly fluctuating, but this natural variation is being exacerbated due to the rapid pace of climate change. As a result, researchers through this study were seeking to determine “if this endangered species will be able to continue using these protected, resource-rich waters, or if they will be forced out into the ocean, which may have major ecological implications for the survival of the species.” They specifically wanted to know if the nursery ground in southeast Tasmania will remain a viable area for school shark pups in the coming years. To reach their conclusion, researchers evaluated the physiology and biochemistry of neonatal and juvenile sharks. 

    “Hopefully, these findings will be able to guide or inform regulations that can improve shark health,” said Katherine Ollerhead, a PhD candidate at the University of Tasmania in Australia and co-author of the study. 

    Physiology is a broad area of scientific inquiry that focuses on how molecules, cells, tissues and organs function in health and disease. The American Physiological Society connects a global, multidisciplinary community of more than 10,000 biomedical scientists and educators as part of its mission to advance scientific discovery, understand life and improve health. The Society drives collaboration and spotlights scientific discoveries through its 16 scholarly journals and programming that support researchers and educators in their work. 

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  • Scientists Find First Evidence That Marine Conservation Mitigates Climate Change

    Scientists Find First Evidence That Marine Conservation Mitigates Climate Change

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    Newswise — Marine protected areas act as a safeguard for oceans, seas, and estuaries. These zones help to preserve the plants and animals that call these waters home, but the benefits of protected areas extend far beyond their boundaries. In a review publishing October 21 in the journal One Earth, a team of researchers explain how marine protected areas help to sequester carbon and foster ecological and social adaption to climate change.

    “Marine protected areas are increasingly being promoted as an ocean-based climate solution. Yet such claims remain controversial due to the diffuse and poorly synthesized literature on climate benefits of marine protected areas,” write the authors. “To address this knowledge gap, we conducted a systematic literature review of 22,403 publications spanning 241 marine protected areas.”

    The authors found that carbon sequestration in marine protected areas increased significantly in seagrass areas, mangroves, and in areas where sediment wasn’t trawled. “Partial or full degradation of mangroves and seagrass both resulted in similar decreases of sequestered carbon, indicating that even low levels of human impact result in important carbon emissions,” they write.

    In addition to boosting carbon sequestration, preserved areas were more biodiverse, had increased species richness, and showed benefits for humans, too. Marine protected areas had greater food security, and fish stocks in waters adjacent to these protected areas swelled. The authors note that the mitigation and adaptation benefits of these protected areas were only achieved under high levels of protection, and that benefits increased the longer an area had been protected.

    “Across all four pathways analyzed, only full and high levels of protection resulted in mitigation or adaptation benefits,” they write. “In contrast, low levels of protection generated no benefits. Furthermore, increases in species richness and in fishers’ income only occurred for fully protected areas, where no fishing is allowed.”

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    One Earth, Jacquemont et al. “Ocean conservation boosts climate change mitigation and adaptation” https://www.cell.com/one-earth/fulltext/S2590-3322(22)00480-8

    One Earth (@OneEarth_CP), published by Cell Press, is a monthly journal that features papers from the fields of natural, social, and applied sciences. One Earth is the home for high-quality research that seeks to understand and address today’s environmental Grand Challenges, publishing across the spectrum of environmental change and sustainability science. A sister journal to Cell, Chem, and Joule, One Earth aspires to break down barriers between disciplines and stimulate the cross-pollination of ideas with a platform that unites communities, fosters dialogue, and encourages transformative research. Visit http://www.cell.com/one-earth. To receive Cell Press media alerts, contact [email protected].

    For the latest sustainability research and ideas from Cell Press follow @CellPressSust on Twitter.

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  • Marine Protected Areas Combat the Effects of Climate Change

    Marine Protected Areas Combat the Effects of Climate Change

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    Newswise — Marine protected areas (MPAs) are one of the solutions being put forward to help adapt to and mitigate the effects of climate change. To demonstrate their effectiveness, scientists from CRIOBE (CNRS/École Pratique des Hautes Etudes/UPVD), as part of an international team1, analysed 22,403 research articles on MPAs. Their results show that MPAs can significantly improve carbon sequestration, coastal protection, biodiversity and the reproductive capacity of marine organisms, as well as the catches and income of fishers when they are fully or highly protected. Although MPAs cannot solely compensate for the full impact of climate change, they are a valuable tool for the mitigation and adaptation of socio-ecological systems. While ocean-related solutions were previously proposed without any real grounding, these results now provide a scientific basis for intergovernmental conventions to address the climate crisis. This new study, published in One Earth on October 21, also reveals that the effect of MPAs on certain climate mechanisms is still not sufficiently documented.

    1This research involved scientists from the Ocean-Climate Platform at the Stockholm Resilience Centre (Stockholm University) and the School of Aquatic and Fishery Sciences (University of Washington).

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