Bioregions in marine environments: Combining Biological and Environmental Data for Management and Scientific Understanding

Bioregions are important tools for understanding and managing natural resources. Bioregions should describe locations of relatively homogenous assemblages of species occur, enabling managers to better regulate activities that might affect these assemblages. Many existing bioregionalization approaches, which rely on expert-derived, Delphic comparisons or environmental surrogates, do not explicitly include observed biological data in such analyses. We highlight that, for bioregionalizations to be useful and reliable for systems scientists and managers, the bioregionalizations need to be based on biological data; to include an easily understood assessment of uncertainty, preferably in a spatial format matching the bioregions; and to be scientifically transparent and reproducible. Statistical models provide a scientifically robust, transparent, and interpretable approach for ensuring that bioregions are formed on the basis of observed biological and physical data. Using statistically derived bioregions provides a repeatable framework for the spatial representation of biodiversity at multiple spatial scales. This results in better-informed management decisions and biodiversity conservation outcomes.Peer reviewe

Transdisciplinarity in transformative ocean governance research—reflections of early career researchers

This paper interrogates the concept of transdisciplinarity, both theoretically and practically, from a perspective of early career researchers (ECRs) in transformative ocean governance research. Aiming to advance research methodologies for future complex sustainability challenges, the paper seeks to illuminate some common uncertainties and challenges surrounding transdisciplinarity from a marine science perspective. Following a literature review on transdisciplinary research, workshops, and a series of surveys, we determine that transdisciplinarity appears to be a concept in search of definition, and that there is a need to explore transdisciplinarity specifically from an ocean research perspective. The paper discusses a number of challenges experienced by ECRs in conducting transdisciplinary research and provides recommendations for both ECRs wishing to undertake more equitable transdisciplinary research and for the UN Decade for Ocean Science to support ECRs in this endeavour (Figure 1). Based on our findings, we interrogate the role of non-academic collaborators in transdisciplinary research and argue that future transdisciplinarity will need to address power imbalances in existing research methods to achieve knowledge co-production, as opposed to knowledge integration

Interannual variability in Indian Ocean surface waters and tuna-environment relationships : filling the gaps with a coupled bio-physical ocean model

Study of the Indian Ocean has lagged behind that of the Atlantic and Pacific, with large knowledge gaps remaining in our understanding of regional or basin-scale controls on productivity and higher trophic levels. A lack of in situ data, especially for mid and upper trophic-level organisms, has commonly limited to small spatiotemporal scales, investigations into environmental control of biological systems. These data gaps are increasingly being filled by coupled bio-physical ocean models. Throughout this thesis, outputs from such a coupled ocean model (NEMO-PISCES) were employed to provide hindcast (1961-2001) records of three-dimensional environmental fields in the Indian Ocean

Indian Ocean Dipole and El Niño/Southern Oscillation impacts on regional chlorophyll anomalies in the Indian Ocean

International audienceThe Indian Ocean Dipole (IOD) and the El Niño/Southern Oscillation (ENSO) are independent climate modes, which frequently co-occur, driving significant inter-annual changes within the Indian Ocean. We use a four-decade hindcast from a coupled biophysical ocean general circulation model, to disentangle patterns of chlorophyll anomalies driven by these two climate modes. Comparisons with remotely sensed records show that the simulation competently reproduces the chlorophyll seasonal cycle, as well as open-ocean anomalies during the 1997/1998 ENSO and IOD event. Results suggest that anomalous surface and euphotic-layer chlorophyll blooms in the eastern equatorial Indian Ocean in fall, and southern Bay of Bengal in winter, are primarily related to IOD forcing. A negative influence of IOD on chlorophyll concentrations is shown in a region around the southern tip of India in fall. IOD also depresses depth-integrated chlorophyll in the 5-10 • S thermocline ridge region , yet the signal is negligible in surface chlorophyll. The only investigated region where ENSO has a greater influence on chlorophyll than does IOD, is in the Somalia upwelling region , where it causes a decrease in fall and winter chlorophyll by reducing local upwelling winds. Yet unlike most other regions examined, the combined explanatory power of IOD and ENSO in predicting depth-integrated chlorophyll anomalies is relatively low in this region, suggestive that other drivers are important there. We show that the chlorophyll impact of climate indices is frequently asymmetric, with a general tendency for larger positive than negative chlorophyll anomalies. Our results suggest that ENSO and IOD cause significant and predictable regional re-organisation of chlorophyll via their influence on near-surface oceanogra-phy. Resolving the details of these effects should improve our understanding, and eventually gain predictability, of interan-nual changes in Indian Ocean productivity, fisheries, ecosystems and carbon budgets

Taking state of biodiversity reporting into the information age – A South African perspective

South Africa’s National Biodiversity Assessment (NBA) is the primary tool for monitoring and reporting on the state of biodiversity, with a focus on spatial information and key indicators. The NBA distills information that informs policies and strategies, meets national and international reporting requirements, and helps prioritize limited resources for managing and conserving biodiversity. The three previous versions of the NBA (2004, 2011 and 2018) are in the form of detailed thematic technical reports and a synthesis report, served on a simple, static web page. Selected spatial products from the report are available via a dedicated web platform (http://nba.sanbi.org.za/). While all methods and data are clearly described in the technical reports, most of the underlying analyses are inaccessible, lacking reproducibility and transparency. This makes iterative updates to indicators or metrics challenging and inefficient, complicates version control, and exacerbates the risk of capacity, knowledge and data loss during staff turnover. To move the assessment process into the information age we aim to develop well documented and reproducible workflows, and to serve the indicators and their accompanying synthesis on an interactive web platform that facilitates uptake. Achieving these aims will deliver efficiency, greater transparency and trust in future NBA products and will strengthen communication and engagement with the content by the many different users of those products. While these visions will not be realized overnight, the skills and systems required to achieve them can be adaptively built towards an improved NBA that better serves the needs of our society

Data from: Persistence of distinctive morphotypes in the native range of the CITES-listed Aldabra giant tortoise

Understanding the extent of morphological variation in the wild population of Aldabra giant tortoises is important for conservation, as morphological variation in captive populations has been interpreted as evidence for lingering genes from extinct tortoise lineages. If true, this could impact reintroduction programmes in the region. The population of giant tortoises on Aldabra Atoll is subdivided and distributed around several islands. Although pronounced morphological variation was recorded in the late 1960s, it was thought to be a temporary phenomenon. Early researchers also raised concerns over the future of the population, which was perceived to have exceeded its carrying capacity. We analyzed monthly monitoring data from 12 transects spanning a recent 15-year period (1998–2012) during which animals from four subpopulations were counted, measured, and sexed. In addition, we analyzed survival data from individuals first tagged during the early 1970s. The population is stable with no sign of significant decline. Subpopulations differ in density, but these differences are mostly due to differences in the prevailing vegetation type. However, subpopulations differ greatly in both the size of animals and the degree of sexual dimorphism. Comparisons with historical data reveal that phenotypic differences among the subpopulations of tortoises on Aldabra have been apparent for the last 50 years with no sign of diminishing. We conclude that the giant tortoise population on Aldabra is subject to varying ecological selection pressures, giving rise to stable morphotypes in discrete subpopulations. We suggest therefore that (1) the presence of morphological differences among captive Aldabra tortoises does not alone provide convincing evidence of genes from other extinct species; and (2) Aldabra serves as an important example of how conservation and management in situ can add to the scientific value of populations and perhaps enable them to better adapt to future ecological pressures

Transdisciplinarity in transformative ocean governance research - reflections of early career researchers

This paper interrogates the concept of transdisciplinarity, both theoretically and practically, from a perspective of early career researchers (ECRs) in transformative ocean governance research. Aiming to advance research methodologies for future complex sustainability challenges, the paper seeks to illuminate some common uncertainties and challenges surrounding transdisciplinarity from a marine science perspective. Following a literature review on transdisciplinary research, workshops, and a series of surveys, we determine that transdisciplinarity appears to be a concept in search of definition, and that there is a need to explore transdisciplinarity specifically from an ocean research perspective. The paper discusses a number of challenges experienced by ECRs in conducting transdisciplinary research and provides recommendations for both ECRs wishing to undertake more equitable transdisciplinary research and for the UN Decade for Ocean Science to support ECRs in this endeavour (Figure 1). Based on our findings, we interrogate the role of non-academic collaborators in transdisciplinary research and argue that future transdisciplinarity will need to address power imbalances in existing research methods to achieve knowledge co-production, as opposed to knowledge integration

Data from: Persistence of distinctive morphotypes in the native range of the CITES-listed Aldabra giant tortoise

Understanding the extent of morphological variation in the wild population of Aldabra giant tortoises is important for conservation, as morphological variation in captive populations has been interpreted as evidence for lingering genes from extinct tortoise lineages. If true, this could impact reintroduction programmes in the region. The population of giant tortoises on Aldabra Atoll is subdivided and distributed around several islands. Although pronounced morphological variation was recorded in the late 1960s, it was thought to be a temporary phenomenon. Early researchers also raised concerns over the future of the population, which was perceived to have exceeded its carrying capacity. We analyzed monthly monitoring data from 12 transects spanning a recent 15-year period (1998–2012) during which animals from four subpopulations were counted, measured, and sexed. In addition, we analyzed survival data from individuals first tagged during the early 1970s. The population is stable with no sign of significant decline. Subpopulations differ in density, but these differences are mostly due to differences in the prevailing vegetation type. However, subpopulations differ greatly in both the size of animals and the degree of sexual dimorphism. Comparisons with historical data reveal that phenotypic differences among the subpopulations of tortoises on Aldabra have been apparent for the last 50 years with no sign of diminishing. We conclude that the giant tortoise population on Aldabra is subject to varying ecological selection pressures, giving rise to stable morphotypes in discrete subpopulations. We suggest therefore that (1) the presence of morphological differences among captive Aldabra tortoises does not alone provide convincing evidence of genes from other extinct species; and (2) Aldabra serves as an important example of how conservation and management in situ can add to the scientific value of populations and perhaps enable them to better adapt to future ecological pressures

Ices meets marine historical ecology: placing the history of fish and fisheries in current policy context

As a discipline, marine historical ecology (MHE) has contributed significantly to our understanding of the past state of the marine environment when levels of human impact were often very different from those today. What is less widely known is that insights from MHE have made headway into being applied within the context of present-day and long-term management and policy. This study draws attention to the applied value of MHE. We demonstrate that a broad knowledge base exists with potential for management application and advice, including the development of baselines and reference levels. Using a number of case studies from around the world, we showcase the value of historical ecology in understanding change and emphasize how it either has already informed management or has the potential to do so soon. We discuss these case studies in a context of the science-policy interface around six themes that are frequently targeted by current marine and maritime policies: climate change, biodiversity conservation, ecosystem structure, habitat integrity, food security, and human governance. We encourage science-policy bodies to actively engage with contributions from MHE, as well-informed policy decisions need to be framed within the context of historical reference points and past resource or ecosystem changes

Working Group on the History of Fish and Fisheries (WGHIST): Expert Group Reports

The ICES Working Group on the History of Fish and Fisheries (WGHIST) is a forum for interdisciplinary research on social-ecological change in marine and fisheries systems over multi-decadal to centennial timescales.WGHIST comprises a diverse group of researchers, including marine biologists, fisheries scientists, historians, and historical ecologists, from Europe and North America, as well as Australia, Russia, and South Africa. WGHIST provided a platform for the sharing and reporting of a wide range of research on marine and fisheries systems change over time, including the use of novel and non-traditional data sources and methodologies to identify and interpret these changes. WGHIST members also worked with the ICES Secretariat to forward digital tools to make historical resources more accessible and regarding WGHIST’s potential to support ICES Fisheries and Ecosystem Overviews.WGHIST engaged with the larger research community on the following manuscripts, still in development or recently submitted: (1) the acute value of the past in the Anthropocene; (2) the importance of and advice on cross-disciplinary conversations; (3) the legacy of Sidney Holt; (4) the power and consequence of qualitative information; and (5) the social and cultural drivers of technology creep.Finally, WGHIST found extensive evidence for defining elements of blue growth in the past, and explored examples from around the world to delineate lessons for today’s blue growth agendas, research now published in Fish and Fisheries. Future work will forward additional digital tools to access historical resources, develop links to other related data resources, and progress connections between lessons from the past and contemporary management and policy