Historically, considerations of the carbon budget of bivalve shellfish have disproportionately focused on the cycling of carbon in shell alone, overlooking respiratory release and the potential role of bivalve shellfish habitats in the stabilization of sediment, and therefore of carbon. Data on carbon cycling are key to providing essential evidence to inform evaluation of management strategies and the business case for restoration of European flat oyster ( Ostrea edulis ) habitats. The purpose of this study was to examine the flat oyster carbon budget at the scale of the individual and to set out a framework to enable future comparisons of carbon budgets between ecosystems. Through the combination of previously established work with measurements of calcification and respiration both in situ and ex situ , a carbon budget at the scale of a single oyster was determined. In consideration of the flat oyster carbon budget, the inclusion of the deposition of sedimentary carbon, as well as carbon stored in shell, balanced with the release of carbon through respiration and calcification suggests that these habitats are unlikely to be significant carbon sinks in the context of global climate change mitigation. However, the recovery of flat oyster beds is likely to facilitate the accretion of substantial carbon stocks that are nevertheless important in conservation management.

This study provides the first report of an egg nursery for the Critically Endangered flapper skate Dipturus intermedius and a description of the habitat, thus contributing towards our understanding of essential habitats for the species. In total, 1,395 flapper skate egg cases were recorded (accounting for overlapping surveys) in two egg case collection dives (n = 67 egg cases), one photogrammetry dive (n = 10 egg cases), 509 drop-down video (DDV) camera drifts (n = 510 egg cases) and 18 remote operated vehicle (ROV) flights (n = 1,031 egg cases), carried out in the Inner Sound on the west coast of Scotland from 2018 to 2021. All of the egg cases were found on a shallow bedrock plateau between the Isle of Scalpay and a deep (>100 m) water channel between the Isle of Longay and the Crowlin Islands. Egg cases were observed on a cobble/boulder reef between 25 and 58 m depth, with a modelled annual temperature range of 9-12 degrees C, modelled current speeds up to 0.2 m(-1), a rugosity index of 1.7 and low levels of sedimentation. Flapper skate egg cases are large and the incubation period is protracted (18 months), making them potentially vulnerable to anthropogenic disturbance. A description of the habitat where egg cases were observed in this study will help inform the search for egg nurseries for this Critically Endangered species elsewhere. Targeted DDV, ROV and scuba diving surveys will support this search in areas where suitable bathymetric and hydrodynamic conditions are identified. Safeguarding egg nurseries is essential for successful conservation. Protection should involve the designation of egg nurseries as Marine Protected Areas where activities that are likely to damage or alter seabed habitats are managed.

Modiolus modiolus (horse mussel) reefs are an example of marine biodiversity hotspots of high conservation importance. Due to historical destruction and slow rates of recovery, the habitat is considered threatened and/or declining under the OSPAR Convention for the Protection of the Marine Environment of the North-East Atlantic 1992, and therefore incorporated into the conservation legislation of several countries. An analysis of genetic connectivity and diversity of nine M. modiolus reefs across Scotland, both within and outside of Marine Protected Areas (MPAs), was undertaken using 12 newly developed microsatellite markers. Analyses indicated moderate to high levels of genetic connectivity between all populations and significantly low genetic variance among populations. Generally, a lack of spatial genetic structure was determined though several populations were highlighted as potentially genetically separated. Structure and connectivity results were largely corroborated by network visualization which additionally identified several potentially key populations. All populations showed departure from Hardy–Weinberg Equilibrium (HWE) and positive inbreeding coefficients, suggesting reduced genetic diversity and/or reflecting the high frequency of null alleles observed across populations. However, allelic richness was uniformly high across all reefs compared to previously reported results for the habitat. Results broadly suggest that an open system of M. modiolus populations exists in Scottish waters and align with conclusions from prior larval dispersal modeling. Findings highlight that neither M. modiolus populations nor the MPAs where they are found should be considered discrete, independent entities and support the protection of features within MPAs in concert with non-designated areas and across varying spatial scales. It is proposed that potential for greater protection exists if all relevant Scottish MPAs, i.e., both those where M. modiolus reefs are a designated feature and those that host M. modiolus reefs, had statutory restrictions on all activities that cause damage to the sea bed. Such protection may facilitate the support of vulnerable populations by more resilient populations, particularly under climate change. Furthermore, given that a large number of unprotected M. modiolus populations may be important components in the interdependent system of reef populations, supplementary genetics studies informed by larval dispersal modeling are recommended to identify further key populations for safeguarding.

Blue carbon is receiving much attention within Agenda 2030 as a nature-based solution (NBS) to climate change, but classically focuses only on seagrass meadows, mangrove forests, and tidal marshes – these are characterised by 2 key ecosystem features (high primary productivity and organic sediment accumulation). However, other ecosystems could also be important but remain neglected in NBS strategic planning. Using meta-analysis, we have identified four additional ecosystem features that enable other non-classical systems – including intertidal mud flats, coralline algae beds / rhodoliths and shallow seabed sediments (particularly fjords) – to play a major role in global blue carbon burial. A paucity of empirical evidence for other coastal systems (coral reefs, bivalve beds, rocky reefs and polar zoobenthos), currently prevents an objective assessment of their role in blue carbon storage. Informed by this, we propose a real-world application framework, including research and management priorities, for fully integrating blue carbon as a NBS to climate change across ecosystems; this will “close the loop” on carbon burial including all contributing non-classical blue carbon ecosystems. Failure to do so will risk a major weakness in the global blue carbon inventory, limiting the effectiveness of any implemented NBS strategies.

Of all the interconnected threats facing the planet, the top two are the climate and the biodiversity crises. Neither problem will be solved if we ignore the ocean. To turn the tide in favour of humanity and a habitable planet, we need to recognize and better value the fundamental role that the ocean plays in the earth system, and prioritize the urgent action needed to heal and protect the ocean at the 'Earthscape' level - the planetary scale at which processes to support life operate. The countries gathering at COP26 have unparalleled political capacity and leadership to make this happen. COP26 could be the turning point, but there must be commitment to united action for the ocean, as well as planning to meet those commitments, based on science-led solutions that address the interconnectivity of the ocean, climate, and biodiversity. Key ways in which the ocean both contributes to and acts as the major buffer for climate change are summarized, focusing on temperature, but not forgetting the role of storing carbon. It is noted with 'high confidence' that the ocean has stored 91% of the excess heat from global warming, with land, melting ice, and the atmosphere only taking up approximately 5, 3, and 1%, respectively. We also highlight the impact of the recent large release of heat from the ocean to the atmosphere during the 2015-2016 El Nino. We then present six science-based policy actions that form a recovery stimulus package for people, climate, nature, and the planet. Our proposals highlight what is needed to view, value, and treat the planet, including the ocean, for the benefit and future of all life.

If you look inside the front cover of Volume 1, issue 1 of Aquatic Conservation: Marine and Freshwater Ecosystems (AQC), published in September 1991, you will find a description of the journal as ‘an international journal dedicated to publishing original papers that relate specifically to the conservation of freshwater, brackish or marine habitats and encouraging work that spans these ecosystems’. That wording has remained the same for the 30 years that the journal has been in existence. Although the range of topic areas and the balance among them have evolved, our objective remains the same. Yet despite the title of the journal and the unambiguous statement that we publish ‘papers that relate specifically to … conservation’, we are often frustrated that the content of the manuscripts received does not match the description clearly given on our website. To put it simply: manuscripts that cannot demonstrate their significance for conservation will not be published in our journal. With respect to their conservation content, manuscripts submitted to AQC can be placed into one of four categories: (i) those that are clearly well outside the scope of the journal, such as papers purely on taxonomy, hydrology or genetics; (ii) those that may have some relevance to conservation but are not appropriate for AQC, such as descriptive papers on water quality and pollution; (iii) those that are relevant to conservation but where the conservation aspects have not been highlighted; and (iv) papers where the conservation aspects are discussed clearly and comprehensively. When manuscripts in categories (i) and (ii) are submitted they are rejected without review. Those in category (iii) will often be reviewed and the authors will be encouraged to redraft the manuscript so that its application to conservation is explicit. The papers that have the best chance of being published are those that fall within category (iv), where sound science is matched by a firm focus on conservation and management and where this is clearly described. The lack of a conservation focus applies to papers on both freshwater and marine topics, but to a different extent. This is reflected in our publication figures. In 2020, manuscripts submitted on freshwater subjects comprised approximately 50% of the total, yet of the 195 articles published 121 (62%) covered marine subjects. In a previous article (Boon & Baxter, 2016), we suggested several factors that may be responsible: marine conservation is a more clearly defined area of study than freshwater conservation; there are site designations exclusively for marine areas; groups and societies have been formed dedicated to conserving marine habitats and species; and the large ‘iconic species’ (such as whales, dolphins and sharks) or habitats (e.g. coral reefs) present are usually those associated with marine rather than freshwater habitats. Whether or not freshwater conservation as an area of study receives the attention it deserves is a debate for another day. That is not the reason for writing this editorial. We are writing it to urge prospective authors to think carefully about the application of their scientific research to conservation, and to make this prominent in the manuscripts they submit to this journal. It is not sufficient that the research has been undertaken in a protected area or on a species of conservation concern. What is required is that there is subsequent discussion of the conservation implications of the results. At the end of our editorial for the 25th anniversary issue, we said: ‘It remains our goal that AQC should continue to publish work of a high standard from all parts of the world, and to encourage scientists to recognize and promote the application of their research to practical conservation and management’ (Boon & Baxter, 2016). Since we wrote that, annual submissions to AQC have risen by more than 50%. With continued growth, there is an even greater need for papers to demonstrate an explicit relevance to conservation if they are to be considered suitable for publication in AQC. We invite our authors to submit manuscripts that do just that.

Over the last 200 years, human activities have released more than 500 billion metric tonnes of carbon dioxide into the atmosphere, of which 27 per cent have been absorbed by the ocean, promoting a cascade of chemical changes known as ocean acidification. These changes are occurring at an unprecedented rate in the last millions of years, and projections indicate that by 2060, seawater acidity could have increased by 120 per cent representing a major threat for the structure and function of marine ecosystems. When facing ocean acidification challenges, it can be expected that there will be both species winners and losers. Those producing shell skeletons, such as corals and molluscs, are some of the most vulnerable groups. Unless they can tolerate these changes or quickly adapt, they will decline and may in time become extinct. The impacts of ocean acidification on molluscs, for example, are not limited to biological traits. Human consumer preferences and market attributes will also be challenged, expanding the impact to socio-ecological systems such as aquaculture and fisheries, which presents major implications for seafood production. Ocean acidification must therefore be recognized as a global challenge that adds extra weight to calls for urgent action to reduce carbon dioxide emissions. In addition, we need to protect, conserve, and enhance both terrestrial and marine natural carbon sinks. Global action on emission reductions must also be coordinated with regional and local measures because of the interaction of ocean acidification with other environmental stressors (e.g., warming, hypoxia, overfishing and pollution). Global and regional scientific collaboration through monitoring and experimentation are essential for improving our knowledge about the impacts of ocean acidification on marine ecosystems. Extensive communication about these findings will be also critical in supporting the development of improved policies and decision-making aimed at establishing adaptation strategies to improve the health of the ocean and marine ecosystems.

Sub-seabed gas is commonly associated with seabed depressions known as pockmarks-the main venting sites for hydrocarbon gases to enter the water column. Sub-seabed gas accumulations are characterized by acoustically turbid or opaque zones in seismic reflection profiles, taking the form of gas blankets, curtains or plumes. How the migration of sub-seabed gas relates to the origin and distribution of pockmarks in nearshore and fjordic settings is not well understood. Using marine geophysical data from Loch Linnhe, a Scottish fjord, we show that shallow sub-seabed gas occurs predominantly within glaciomarine facies either as widespread blankets in basins or as isolated pockets. We use geospatial 'hot-spot' analysis conducted in ArcGIS to identify clusters of pockmarks and acoustic (sub-seabed) profile interpretation to identify the depth to gas front across the fjord. By combining these analyses, we find that the gas below most pockmarks in Loch Linnhe is between 1.4 m and 20 m deep. We anticipate that this work will help to understand the fate and mobility of sedimentary carbon in fjordic (marine) settings and advise offshore industry on the potential hazards posed by pockmarked seafloor regions even in nearshore settings.

Aquatic Conservation: Marine and Freshwater EcosystemsVolume 31, Issue 8 p. 2302-2303 COMMENTARY AND CORRESPONDENCE ARTICLE Response to Ota, Allison and Fabinyi on 'Evolving the narrative for protecting a rapidly changing ocean, post COVID-19' Dan Laffoley, Corresponding Author Dan Laffoley [email protected] orcid.org/0000-0001-6338-6244 IUCN World Commission on Protected Areas, IUCN (International Union for Conservation of Nature), Gland, Switzerland Correspondence Dan Laffoley, IUCN World Commission on Protected Areas, International Union for Conservation of Nature, 28 rue Mauverney, CH-1196, Gland, Switzerland. Email: [email protected]Search for more papers by this authorJohn M. Baxter, John M. Baxter orcid.org/0000-0002-0847-3318 Marine Alliance for Science and Technology for Scotland, School of Biology, East Sands, University of St Andrews, Fife, UKSearch for more papers by this authorDiva J. Amon, Diva J. Amon orcid.org/0000-0003-3044-107X Department of Life Sciences, Natural History Museum, London, UKSearch for more papers by this authorJoachim Claudet, Joachim Claudet orcid.org/0000-0001-6295-1061 National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, Paris, FranceSearch for more papers by this authorJason M. Hall-Spencer, Jason M. Hall-Spencer orcid.org/0000-0002-6915-2518 School of Marine and Biological Sciences, University of Plymouth, Plymouth, UK Shimoda Marine Research Center, University of Tsukuba, Tsukuba, JapanSearch for more papers by this authorKirsten Grorud-Colvert, Kirsten Grorud-Colvert orcid.org/0000-0002-4234-4499 Department of Integrative Biology, Oregon State University, Corvallis, Oregon, USASearch for more papers by this authorLisa A. Levin, Lisa A. Levin orcid.org/0000-0002-2858-8622 Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USASearch for more papers by this authorP. Chris Reid, P. Chris Reid orcid.org/0000-0001-7728-6746 School of Marine and Biological Sciences, University of Plymouth, Plymouth, UK The Continuous Plankton Recorder Survey, Marine Biological Association, The Laboratory, Plymouth, UKSearch for more papers by this authorAlex D. Rogers, Alex D. Rogers Somerville College, University of Oxford, Oxford, UK REV Ocean, Lysaker, NorwaySearch for more papers by this authorMichelle L. Taylor, Michelle L. Taylor orcid.org/0000-0001-7271-4385 University of Essex, Colchester, UKSearch for more papers by this authorLucy C. Woodall, Lucy C. Woodall orcid.org/0000-0001-7295-7184 Department of Zoology, University of Oxford, Zoology Research and Administration Building, Oxford, UKSearch for more papers by this authorNatalie F. Andersen, Natalie F. Andersen orcid.org/0000-0003-1288-2568 Department of Environment and Geography, University of York, York, UK Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UKSearch for more papers by this author Dan Laffoley, Corresponding Author Dan Laffoley [email protected] orcid.org/0000-0001-6338-6244 IUCN World Commission on Protected Areas, IUCN (International Union for Conservation of Nature), Gland, Switzerland Correspondence Dan Laffoley, IUCN World Commission on Protected Areas, International Union for Conservation of Nature, 28 rue Mauverney, CH-1196, Gland, Switzerland. Email: [email protected]Search for more papers by this authorJohn M. Baxter, John M. Baxter orcid.org/0000-0002-0847-3318 Marine Alliance for Science and Technology for Scotland, School of Biology, East Sands, University of St Andrews, Fife, UKSearch for more papers by this authorDiva J. Amon, Diva J. Amon orcid.org/0000-0003-3044-107X Department of Life Sciences, Natural History Museum, London, UKSearch for more papers by this authorJoachim Claudet, Joachim Claudet orcid.org/0000-0001-6295-1061 National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, Paris, FranceSearch for more papers by this authorJason M. Hall-Spencer, Jason M. Hall-Spencer orcid.org/0000-0002-6915-2518 School of Marine and Biological Sciences, University of Plymouth, Plymouth, UK Shimoda Marine Research Center, University of Tsukuba, Tsukuba, JapanSearch for more papers by this authorKirsten Grorud-Colvert, Kirsten Grorud-Colvert orcid.org/0000-0002-4234-4499 Department of Integrative Biology, Oregon State University, Corvallis, Oregon, USASearch for more papers by this authorLisa A. Levin, Lisa A. Levin orcid.org/0000-0002-2858-8622 Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, USASearch for more papers by this authorP. Chris Reid, P. Chris Reid orcid.org/0000-0001-7728-6746 School of Marine and Biological Sciences, University of Plymouth, Plymouth, UK The Continuous Plankton Recorder Survey, Marine Biological Association, The Laboratory, Plymouth, UKSearch for more papers by this authorAlex D. Rogers, Alex D. Rogers Somerville College, University of Oxford, Oxford, UK REV Ocean, Lysaker, NorwaySearch for more papers by this authorMichelle L. Taylor, Michelle L. Taylor orcid.org/0000-0001-7271-4385 University of Essex, Colchester, UKSearch for more papers by this authorLucy C. Woodall, Lucy C. Woodall orcid.org/0000-0001-7295-7184 Department of Zoology, University of Oxford, Zoology Research and Administration Building, Oxford, UKSearch for more papers by this authorNatalie F. Andersen, Natalie F. Andersen orcid.org/0000-0003-1288-2568 Department of Environment and Geography, University of York, York, UK Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UKSearch for more papers by this author First published: 09 June 2021 https://doi.org/10.1002/aqc.3607Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. REFERENCES Bennett, N.J., Blythe, J., White, C.S. & Campero, C. (2021). Blue growth and blue justice: Ten risks and solutions for the ocean economy. Marine Policy, 125, 104387. https://doi.org/10.1016/j.marpol.2020.104387 10.1016/j.marpol.2020.104387 Web of Science®Google Scholar Laffoley, D., Baxter, J.M., Amon, D.J., Claudet, J., Hall-Spencer, J.M., Grorud-Colvert, K. et al. (2020). Evolving the narrative for protecting a rapidly changing ocean, post COVID-19. Aquatic Conservation: Marine and Freshwater Ecosystems, 1–23. https://doi.org/10.1002/aqc.3512 Web of Science®Google Scholar Ota, Y., Allison, E.H. & Fabinyi, M. (2021). Evolving the narrative for protecting a rapidly changing ocean, post COVID-19. Aquatic Conservation: Marine and Freshwater Ecosystems, 1–2. https://doi.org/10.1002/aqc.3568 Web of Science®Google Scholar Rudolph, T.B., Ruckelshaus, M., Swilling, M., Allison, E.H., Österblom, H., Gelcich, S. et al. (2020). A transition to sustainable ocean governance. Nature Communications, 11(1), 3600. https://doi.org/10.1038/s41467-020-17410-2 10.1038/s41467-020-17410-2 CASPubMedWeb of Science®Google Scholar Sterling, E.J., Pascua, P., Sigouin, A., Gazit, N., Mandle, L., Betley, E. et al. (2020). Creating a space for place and multidimensional well-being: Lessons learned from localizing the SDGs. Sustainability Science, 15(4), 1129–1147. https://doi.org/10.1007/s11625-020-00822-w 10.1007/s11625-020-00822-w Web of Science®Google Scholar Volume31, Issue8August 2021Pages 2302-2303 ReferencesRelatedInformation

Anthropogenic climate change presents a major challenge to coastal ecosystems. Mass population declines or geographic shifts in species ranges are expected to occur, potentially leading to wide-scale ecosystem disruption or collapse. This is particularly important for habitat-forming species such as free-living non-geniculate coralline algae that aggregate to form large, structurally complex reef-life ecosystems with high associated biodiversity and carbon sequestration capability. Coralline algal beds have a worldwide distribution, but have recently experienced global declines due to anthropogenic pressures and changing environmental conditions. However, the environmental factors controlling coralline algal bed distribution remain poorly understood, limiting our ability to make adequate assessments of how populations may change in the future. We constructed the first species distribution model for non-geniculate coralline algae (focusing on maerl-forming species but including crustose coralline algae associated with coralline algal beds) and showed that bathymetry, temperature at the seabed and light availability are the primary environmental drivers of present-day non-geniculate coralline algae distribution. Our model also identifies suitable areas for species presence that currently lack records of occurrence. Large-scale spatial declines in coralline algal distribution were observed under all IPCC Representative Concentration Pathways (ranging from 38% decline under RCP 2.6 up to 84% decline under RCP 8.5), with the most rapid rate of decline up to 2050. Refuge populations that may persist under projected climate change were also identified – informing priority areas for future conservation efforts to maximize the long-term survival of this globally important ecosystem.

Globally, momentum to restore damaged habitats has been increasing. For example, the number of European shellfish restoration projects has quadrupled in the past 3 years. In line with the increasing focus on both restoration and climate change mitigation efforts, this study highlights how these two practices can complement each other. This experimental study quantifies the active and passive sediment deposition associated with the European flat oyster (Ostrea edulis) and the organic and inorganic carbon fractions of the deposits. Treatments included 'dead', 'live', and control to account for (i) passive deposition, (ii) biodeposition and passive deposition, and (iii) background deposition respectively. By utilizing these data, the expected carbon deposition associated with a restored flat oyster bed was investigated. The experiment was conducted ex situ, with natural seawater input. Covariate data on temperature, suspended particulate influx, salinity, and oxygen availability were recorded. Enhanced sedimentation (2.9 times) and organic carbon deposition (three times) were observed in the presence of living oysters, compared with the control. The shell structure of the oysters had no influence on passive sedimentation in this study. By developing a full understanding of the ecosystem services (functioning, supporting, regulating, and cultural) provided by a habitat, it becomes possible to quantify overall ecosystem function. This evidence is key in advising policymakers, restoration funders, and marine spatial planners on the connection between keystone species restoration, ecosystem service restoration, and conservation management. The enhancement of benthopelagic coupling by the European flat oyster, evidenced here for the first time, is contextualized from the perspective of quantification of ecosystem service provision for both restoration practices and blue carbon store management. The data produced in this study are discussed comparatively with work that has focused on other species from both Europe and the USA.

The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales. Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future. We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public. Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing. By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.

The ocean is the linchpin supporting life on Earth, but it is in declining health due to an increasing footprint of human use and climate change. Despite notable successes in helping to protect the ocean, the scale of actions is simply not now meeting the overriding scale and nature of the ocean's problems that confront us.Moving into a post-COVID-19 world, new policy decisions will need to be made. Some, especially those developed prior to the pandemic, will require changes to their trajectories; others will emerge as a response to this global event. Reconnecting with nature, and specifically with the ocean, will take more than good intent and wishful thinking. Words, and how we express our connection to the ocean, clearly matter now more than ever before.The evolution of the ocean narrative, aimed at preserving and expanding options and opportunities for future generations and a healthier planet, is articulated around six themes: (1) all life is dependent on the ocean; (2) by harming the ocean, we harm ourselves; (3) by protecting the ocean, we protect ourselves; (4) humans, the ocean, biodiversity, and climate are inextricably linked; (5) ocean and climate action must be undertaken together; and (6) reversing ocean change needs action now.This narrative adopts a 'One Health' approach to protecting the ocean, addressing the whole Earth ocean system for better and more equitable social, cultural, economic, and environmental outcomes at its core. Speaking with one voice through a narrative that captures the latest science, concerns, and linkages to humanity is a precondition to action, by elevating humankind's understanding of our relationship with 'planet Ocean' and why it needs to become a central theme to everyone's lives. We have only one ocean, we must protect it, now. There is no 'Ocean B'.

1. This article introduces a special issue ofAquatic Conservation: Marine and Freshwater Ecosystems(AQC) whose contributions demonstrate examples of the practical impact of the authors' previous AQC articles on the conservation of aquatic ecosystems. 2. The submitting authors of all articles published in AQC since 2009 were invited to express their interest in writing an article for the special issue. The 20 articles selected for publication discuss 33 AQC articles published from 2004 to 2019, spanning a wide range of geographical locations, habitat types, species groups, and impacts on aquatic conservation. 3. The two impacts reported most frequently are 'Undertaking practical management of habitats and species' and 'Establishing partnerships', closely followed by 'Restoring habitats/reintroducing or translocating species'. Many authors demonstrate the importance of their articles in raising awareness across an extensive range of organizations. 4. Some impacts occur soon after publication (e.g. introduction of conservation guidelines), whereas others (e.g. influencing policy) take far longer. Authors report a wide range of methods for disseminating research results appropriate for different audiences, such as technical handbooks, seminars, magazine articles, media broadcasts, and field workshops. 5. To assess whether 'conventional' measures of impact match authors' perceptions, three metrics were calculated for the 33 AQC articles discussed in this issue: the number of citations, the number of downloads, and the Altmetric Attention Score. These metrics were not significantly higher for the 33 articles than the corresponding median metrics of the articles in the issues in which the 33 were published. 6. The goal of AQC is to continue to encourage scientists to recognize and promote the application of their research to practical conservation and management. Given the growing threats to aquatic ecosystems, much remains to be done to make this process even more effective.

That scientific knowledge grows by building on previous understanding is familiarly expressed in English by Isaac Newton's phrasing of a much older idea, "If I have seen further it is by standing on the shoulders of giants." However, in science, we often do not always clamber as high as we could because we fail to consider previous work. Multiple factors beyond quality and relevance affect the likelihood of a scientific article being cited, including the author's status, country, and affiliation (Leimu & Koricheva 2005), number of authors (Neiminen et al. 2007; Sala & Brooks 2008), journal prestige (Tahamtan et al. 2016), length (Neiminen et al. 2007; Stanek 2008), language (van Leeuwen et al. 2001), geographical location of authors and readers (Nunez et al. 2019), direction and strength of the results (Neiminen et al. 2007), accessibility, and whether the article is a self-citation (Schreiber 2009). Furthermore, cited articles are not always used correctly. In ecology (Todd et al. 2007) and marine biology (Todd et al. 2010), 16–18% of citations offer either ambiguous or no support for an associated assertion. Even when articles are debunked, the original papers continue to be cited 17 times more than the rebuttal (Banobi et al. 2011). We suggest that such failings distort knowledge. Few conservation practitioners cite original studies (Pullin et al. 2004; Sutherland 2004), although there is some evidence this is starting to change (Wainwright et al. 2018). Furthermore, most conservation scientists use previous literature selectively, leading to bias (Gossa et al. 2015). We checked the most recent issue of 5 major conservation journals and found 23 papers testing conservation interventions. Together, authors of these papers failed to cite at least 51 other studies, collected on www.conservationevidence.com that tested the same interventions in similar environments. Such underutilization exaggerates the originality of new findings and distorts impressions of existing knowledge and may result in actions being biased toward the single latest study. Poor citation practices have distorted ideas (Smith & Banks 2017), such as that Darwin developed his theory of evolution by looking at Galapagos finches, despite not mentioning them in The Origin of Species (Sulloway 1983); that exotic ants in Madeira were responsible for the extinction of native ants, which never actually went extinct (Wetterer 2006); and that black rats were important predators of Australian mammals, based on a study that found no significant effect of rats on native mammal numbers (Smith & Banks 2017). The failure to assess the existing evidence base fully can lead to an overemphasis on outlying, well publicized, or even discredited studies or those published in prestigious outlets. Effective policy and management rarely emerge from single, definitive experiments. Rather, reliable knowledge accumulates from diverse sources of evaluated evidence that persuade communities of professionals (Collins & Pinch 2012; Roche et al. 2019). We can best understand how to employ interventions by evaluating how they have worked in a range of circumstances. For example, an article on the efficacy of streamer lines in reducing bycatch of seabirds should incorporate previous studies of streamer lines in different locations, with different species, and with different numbers of lines or types of line so as to provide a comprehensive picture of whether the action is generally effective or more effective in some situations than others. In this way, the giant is assembled, and future researchers can avoid pitfalls and target knowledge gaps. Reliability is important and conservation science should encourage studies that replicate interventions (Baker 2016). One solution is the Conservation Evidence website (www.conservationevidence.com) (Sutherland et al. 2019), which was developed to collect, curate, and summarize tests of conservation interventions. It provides a means of checking the literature. Authors may summarize the existing literature by referring to the individual papers or, if the literature is extensive, make use of the review provided. We envisage a simple, routine check of Conservation Evidence and then addition of other relevant literature. Researchers can use it to check they have not missed key references and may reference the webpage to avoid adding references to their manuscript. Conservation Evidence focuses exclusively on conservation solutions, and does not, for example, collect papers describing threats or compile or summarize conceptual and theoretical papers for hypothesis generation and inference. It does not yet cover interventions for all habitats and taxa, and there may be relevant papers published since a literature was synthesized by Conservation Evidence. Other options for extracting the relevant literature include systematic reviews (especially those collated by the Collaboration for Environmental Evidence [www.environmentalevidence.org]); other specialist websites, such as the Resource database of the Society for Ecological Restoration (https://www.ser-rrc.org/resource-database) or the CABI Invasive species compendium (https://www.cabi.org/isc); standard literature searches (ideally with the search process specified); and the forthcoming Applied Ecology Resources (https://www.britishecologicalsociety.org/publications/applied-ecology-resources/), which will host a searchable and citable repository of gray literature. Forty conservation-focused journals, whose lead editors are authors on this editorial (journal names are italicized in the list of author affiliations), are requesting that authors outline how they have placed the literature in context (e.g., by searching Conservation Evidence) by incorporating this in the submission process or in instructions to authors. Asking authors who have tested interventions to explain how they have placed their paper in context will help ensure conservation science reduces the perils of cherry picking scientific evidence and will improve the design of future work. It will not provide a complete remedy to bias in conservation articles. Ideally, the impact of this measure will grow as the evidence base grows, so that we can have the extended vision that comes from standing on the shoulders of giants rather than the limited vision from standing on their toes. We thank Arcadia for funding and the referees for improving this piece.

Pockmarks are seabed depressions that represent primary evidence of rapid biogenic/thermogenic gas build up and fluid release from seabed sediments to the water column. We use a Geographical Information System (GIS) to analyse multibeam echo-sounder bathymetric data and use a range of semi-automated tools to map seabed pockmarks in fjords and adjacent coastal waters around western Scotland. We map 1019 individual pockmarks in 12 different hydrographic areas covering ca. 2019 km(2). We use morphological metrics and statistical procedures to classify and analyse the variety of pockmark forms. A k-means clustering algorithm identifies three classes of pockmark morphology: deep, elongate and regular. The recognition of separate pockmark classes could aid understanding of their age, activity and origin. This work presents the first detailed mapping of pockmark fields in Scottish west coast waters and highlights the use of pockmarks as an indicator of the quantity, mobility and fate of stored carbon.

Marine ecosystems and the services they provide contribute greatly to human well-being but are becoming degraded in many areas around the world. The expansion of Marine Protected Areas (MPAs) has been advanced as a potential solution to this problem but their economic feasibility has hardly been studied. We conduct an economic assessment of the costs and benefits of six scenarios for the global expansion of MPAs. The analysis is conducted at a high spatial resolution, allowing the estimated costs and benefits to reflect the ecological and economic characteristics and context of each MPA and marine ecosystem. The results show that the global benefits of expanding MPAs exceed their costs by a factor 1.4–2.7 depending on the location and extent of MPA expansion. Targeting protection towards pristine areas with high biodiversity yields higher net returns than focusing on areas with low biodiversity or areas that have experienced high human impact.

Saltmarshes are biogeomorphic ecosystems comprising halophytic plant communities typically located on low energy temperate coasts. Their distribution and structure are controlled by several key drivers, including sediment supply, type of vegetation, elevation, and local hydrodynamics. These dynamic systems are highly vulnerable and estimated to be experiencing annual losses of 1-2% globally. Past restoration efforts have largely implemented managed realignment strategies, however, examples of, and research on, conservation initiatives employing direct transplantation of saltmarsh vegetation into damaged or receding saltmarsh stands is less common. Here an example of transplantation restoration was investigated to understand its influence on sediment dynamics. Sediment settlement, deposition, and accretion rates of natural and restored vegetation (Bolboschoenus maritimus) and adjacent bare mudflats in a small estuary system were studied across consecutive seasons from summer 2015 to spring 2016 to examine the success of transplantation. Natural areas of B. maritimus were shown to be most effective at retaining deposited material, although experiencing the least amount of deposition (an average of 48 g/m(2) per day), accreting by nearly 7.5 mm over the experimental period. Mudflat areas experienced the most deposition (an average of 322 g/m(2) per day) whilst exhibiting the greatest erosion over the study, a decrease in level of 6 mm. Restored areas experience similar rates of deposition as their natural counterparts, however, did not retain this material as efficiently, presenting an erosion of 1.6 mm. The study indicates certain biogeomorphic processes have been altered within the restored area and beginning to reflect those of the natural area. However, the restored vegetation does not yet fully match the functionality of the natural B. maritimus stand, specifically where the natural stand displayed a net accretion of material the restored area did not. Such discrepancies may impact on the continued survival of the restoration site, which may have implications for the potential of transplanting to deliver ecosystem services, such as climate change mitigation through carbon burial.