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Abstract The Benguela Current Large Marine Ecosystem (BCLME) is subject to moderate to high levels of fishing, mining and numerous other human pressures, all of which are set to intensify through current socio-economic development initiatives in Angola, Namibia and South Africa. There is, however, minimal spatial protection of marine and coastal ecosystems in the region, potentially reducing the sustainability of the planned development and the likelihood of achieving Sustainable Development Goals. As a precursor to Marine Spatial Planning (MSP) processes in the three countries, and to guide establishment of Marine Protected Areas (MPAs), this study aimed to: assess two headline indicators of ecosystem status, namely their potential threat status and current spatial protection levels; and to use Systematic Conservation Planning (SCP) to prioritise specific areas for protection to achieve networks of MPAs that are representative of national and regional biodiversity. Two hundred and forty eight ecosystem types in the coastal (n = 134), offshore benthic (n = 86) and pelagic (n = 28) zones of the BCLME were classified, mapped and assessed. Overall, 35% of all ecosystem types in the study domain were threatened, with more threatened coastal (37%) and offshore benthic (37%) ecosystem types compared to pelagic ecosystem types (14%), although the same pattern was not necessarily evident within each country. Nearly two thirds (59%) of the BCLME ecosystem types were not protected in MPAs, and most of those that were well (19%) or moderately protected (14%) were coastal types that are within a single extensive MPA in Namibia. Notwithstanding, there was still a sufficient area of most ecosystem types that was assessed to be in good ecological condition in all three countries and that could be prioritised for representative protection of the region's biodiversity. A portfolio of priority conservation areas was identified from Marxan selection-frequency outputs, providing a spatial vision for protected areas in the BCLME that includes coastal, inshore and offshore areas in all three countries. This first assessment of marine ecosystem threat and protection status for an entire LME demonstrates a rapid science-based approach that can inform integrated ocean management and multiple development goals. The study provides a basis for identifying Ecologically or Biologically Significant Marine Areas, potential sites for MPAs or other spatial management in the region, and demonstrates the contribution of SCP and spatial management to MSP. Highlights • 248 ecosystem types were mapped for the Benguela Current Large Marine Ecosystem. • Coastal and offshore benthic ecosystem types are more threatened than pelagic types. • Offshore ecosystem types have less protection than coastal ecosystem types. • 59% of ecosystem types are not represented in MPAs; 19.0% are well represented. • Priority areas are identified to protect biodiversity in the BCLME. [ABSTRACT FROM AUTHOR]

• Ecological Infrastructure (EI) is a promising framework to map ecosystem services. • EI was defined in the context of place-based conservation and management. • EI performance evaluation should include information on demand, flow and capacity. • EI should be prioritised through a systematic spatial prioritisation process. • 16 recommendations were made for mapping EI. Ecosystem services are an important nexus between people and nature. Nevertheless, their inclusion in place-based conservation and management is limited also because they are often intangible. The Ecological Infrastructure (EI) concept is a promising framework to address this, but a clear definition and mapping approach is still missing. We aim to analyse the uses of EI and to distil a definition and recommendations for using EI as a framework for mapping ecosystem services. A semi-systematic review of peer-reviewed and grey literature was conducted to examine: (1) perceptions of what constitutes EI (n = 117), and (2) EI mapping approaches (n = 51). The main interpretations of EI indicated that it should be natural or naturally functioning (56%); deliver multiple services (75%); and benefit humans (64%) and biodiversity (36%). EI was thus defined as 'natural and naturally functioning ecological systems or networks of ecological systems that deliver multiple services to humans and enable biodiversity persistence'. Studies have used simple proxies, e.g., land cover, to identify EI, sometimes combined with service-specific variables. To evaluate EI performance (26% of studies), modelling all three ecosystem service aspects (capacity, flow, and demand) was considered appropriate. EI prioritisation (50% of studies) as part of a systematic spatial prioritisation process was recommended. Sixteen recommendations for mapping EI for inclusion in place-based conservation and management were developed. We illustrate how EI can be used to integrate ecosystem services into conservation and management in three real-world applications. The EI-based framework is a promising approach and supports the new 'people and nature' era in conservation. [ABSTRACT FROM AUTHOR]

We analyze the sustainable seafood movement as a maturing social-ecological issue. Using a timeline of events over more than a decade and other indicators of growth, we identified key points during its six developmental stages, and evidence of entrance into the final (Normative) phase. After distilling and evaluating the main criticisms and claims attributed to sustainable seafood initiatives globally, we concur that the movement has successfully cultivated a demand for solutions to the challenges of seafood sustainability by creating novel interactions along the value chain – even with the modest investment of our South African example. The global movement is best considered as a dynamic process with interplay at multiple spatial and temporal scales, and asynchronous phases of maturation. We recommend future investment in compliance, governance, credibility, and trust-building as key interventions to reduce risks of problem displacement, in support of a stable Normative phase across the seafood supply chain. [ABSTRACT FROM AUTHOR]

Systematic conservation planning (SCP) to design marine protected areas (MPAs) has traditionally focused on species distributions or benthic habitat features that drive the determination of conservation priorities. Pelagic ecosystem protection is usually incidental because these ecosystems are often data-poor and are difficult to visualize in a planning context. Pelagic ecosystems, however, face increasing and cumulative impacts from threats such as overfishing and climate change, and a precautionary approach is required to protect both known and unknown biodiversity patterns and ecosystem processes. Data-driven pelagic habitat classifications are important when planning for habitat protection in the absence of sufficient in-situ data. In this study, we describe a method for creating a bioregional map of the upper-mixed layer of South Africa's pelagic realm. We selected relevant variables and parameters that best reflect key ecosystem properties at broad, meso, and local scales. We conducted a hierarchal cluster analysis using open-access sea surface temperature (SST), chlorophyll- a (chl- a ), net primary productivity (NPP), mean sea level anomalies (MSLA), and seabed slope and depth data. The resulting map delineates three bioregions subdivided into seven biozones and sixteen pelagic habitats within South Africa's continental Exclusive Economic Zone (EEZ). This habitat map was incorporated into SCP of a proposed expanded MPA network that includes offshore protected areas and meets National objectives. The proposed network will increase protection of the pelagic realm (>30 m depth) of the EEZ from 0.002% to 6.0%. We contend that bioregional analyses based on publicly available remote-sensing data are useful for identification of offshore habitats, especially when robust biological data are unavailable, as a framework for ecosystem reporting, and for inclusion in a systematic design for a representative offshore MPA network. Further research should focus on modelling and mapping the permanence of pelagic habitats and different spatio-temporal scales of variability, validating habitat boundaries with biological data, and understanding the threats and efficacy of achieving pelagic protection through management mechanisms like MPAs. [ABSTRACT FROM AUTHOR]

As countries commit to developing their ocean-based economies sustainably, it is critical to secure the underlying marine biodiversity and ecological processes. Ecosystem-based Marine Spatial Planning (MSP) can support achieving this; however, because competition for ocean space is increasing, biodiversity prioritisation must be spatially efficient, conflict-averse, and robust to secure marine biodiversity appropriately. South Africa has a long history and real-world success in spatial planning on land; we aim to draw on this experience to develop an approach by which the biodiversity sector's input to MSP can be developed, in the context of MSP unfolding in South Africa. We used Marxan to develop the first National Coastal and Marine Map of Critical Biodiversity Areas (CBAs) and Ecological Support Areas (ESAs). There were 976 biodiversity features and design elements, and the cost layer aimed to avoid conflict with 19 sea-use sectors and avoid more heavily impacted areas. Biodiversity targets were met in 27.0% of the planning domain (5.4% Marine Protected Areas (MPAs), 21.6% CBAs), with 6.6% for ESAs. Sea-use guidelines were developed based on a matrix of activity compatibility with the management objective for CBAs (keep or restore to natural) and ESAs (avoid further degradation), with MPAs managed through their gazetted regulations. The CBA Map and sea-use guidelines formed the basis for the marine biodiversity sector plan for inclusion in MSP. This approach can be broadly applied, even with limited data, as the basis for multi-sector negotiations. We share seven recommendations from our experience to guide planners from other countries. [Display omitted] • A framework for developing the biodiversity sector's input to MSP is conceptualised. • Efficient network of marine biodiversity priorities is identified for South Africa. • Priorities comprise: MPAs; Critical Biodiversity Areas; Ecological Support Areas. • Sea-use guidelines: based on activity compatibility with zone management objectives. • Outputs are the basis for formal multi-sector stakeholder engagement. [ABSTRACT FROM AUTHOR]

In an increasingly crowded ocean facing global drivers for economic expansion, many fisheries could benefit from spatial management that enhances traditional fisheries management strategies. In order to reduce risks to ocean health and promote social-ecological resilience, a diversity of spatial management instruments is needed to provide rapid responses and longer-term interventions that promote sustainability and security. To support marine spatial planning (MSP) in South Africa, existing legal instruments were investigated by: (i) describing the prevailing legal framework for spatial fisheries management; (ii) identifying existing legal instruments that are or could be implemented to support spatial fisheries management; (iii) assessing the way in which these instruments could be implemented; and (iv) providing research recommendations to enhance integration of fisheries management measures into MSP. Seven Acts were examined. Within these, nine instruments support fisheries management. Six instruments that could directly contribute to spatial fisheries management were analysed for diversity by comparing them against seven criteria that reflect the complexity and time for implementation, longevity in terms of security and permanence and, transgression consequences. Results show that there is a diversity of instruments available that, if used together in an integrated MSP framework, can provide rapid responses as well as address longer-term goals. Although South Africa does have diversity in the instruments available, two of them, namely fisheries management areas (FMAs) and priority fishing areas (PFAs), have never been implemented, representing missed opportunities. As South Africa begins to implement its new MSP process, we recommend integration of FMAs and PFAs in this process. [ABSTRACT FROM AUTHOR]

The extent of biofouling on recreational vessels has been used as a proxy for the presence of alien species and has been linked with vessel characteristics. However, the relationship between these factors and alien species numbers has not been examined, despite the importance of this metric for invasive species management. This study assessed physical characteristics, maintenance regimes and travel patterns of yachts and their relationship with the number of macro-invertebrate alien species present on vessels from four South African marinas. Overall, 88% of yachts were fouled with macro-invertebrate alien species. The only factor that influenced alien species numbers in the context of this study was the primary use of yachts, with cruising yachts supporting significantly more alien species than racing yachts. This is likely linked to differences in cleaning regimes, as racers are subject to rigorous and frequent cleaning. These findings suggest that cruising vessels may play a key role in the intra-regional transfer of alien species and that racing yachts likely pose a lower biosecurity threat. • The use of yachts was the only factor explaining alien species richness. • Cruising vessels supported significantly more alien species than did racers. • Travel among local marinas by these vessels poses an intra-regional transfer risk. • The elevated invasion risk associated with cruisers needs to be managed. [ABSTRACT FROM AUTHOR]

• Responsive indicators need to be identified to define good ecological condition. • Fish metrics responded better to pressure gradients than benthic community metrics. • Size-based metrics were more suitable than compositional metrics of reef condition. • Higher biomass, length & proportion of mature target fish represent good condition. • Identification of possible indicators for Essential Biodiversity Variables (EBVs) Baseline data for reference conditions are needed to determine the impacts of human pressures on the structure and functioning of marine ecosystems. However, baseline data are seldom available, and a comprehensive understanding of what good ecological condition is or how to measure it is often lacking. In the absence of true baselines, well established and effective marine protected areas (MPAs) can be used to approximate reference conditions. Thus, the aim of this study was to use effective no-take MPAs to identify suitable indicators that can be used for condition assessments of rocky reefs in South Africa. To achieve this, we tested the response of two types of metrics (compositional and size-based), using in situ fish and benthic community data, to three levels of human pressures in two ecoregions in South Africa. Results showed that traditionally-used structural metrics, such as total abundance or species richness, were less responsive than size-based metrics, including total biomass, average length and proportion of mature fish. Rocky reef ecosystems exposed to low anthropogenic pressure were characterised by a higher biomass, average length and proportion of mature and large (>30 cm) fish than reefs with moderate and high pressures. Benthic communities appeared more resilient than fish communities to the typical human pressures in the study region. Overall, the greatest effect of pressure was observed in the heavily impacted sub-tropical Natal Shelf Ecoregion, while rocky reefs in the warm-temperate Agulhas Shelf Ecoregion appeared to be in better condition than expected. This study identified assemblage patterns and indicators that appeared responsive and sensitive to different levels of human pressure, which can be used to infer good and poor ecological condition of rocky reef ecosystems. These results indicate which species (e.g., target species) and traits (e.g., size) are most vulnerable to local human pressures and will be suitable for condition assessments. [ABSTRACT FROM AUTHOR]

Abstract Climate change and fishery impacts modify the spatial distribution of marine species. Understanding and predicting changes in distribution is important for adaptation by fishers and the management of fishery resources and biodiversity. However, identifying such trends is challenging given the variability inherent in trawl survey data. We apply a novel two-step approach to identify fish distribution trends from trawl surveys. First, species-specific average locations (mean latitude and longitude centre of gravity) and extent (effective area occupied) were estimated within a spatio-temporal delta modelling framework. The resulting time series and associated variance estimates were then passed to a multivariate Bayesian state-space model to estimate average trends over the study period. We applied this two-stage approach to three decades (1986–2016) of demersal trawl research survey data from the Agulhas Bank of South Africa to quantify distributional changes in 44 commonly caught fishes (chondrichthyans and teleosts). Across the entire assemblage, average trends showed a westward (alongshore) shift in location and a reduction in the extent of populations. At the species level, six taxa showed a location trend towards the west or south-west, and three shifted towards the east or north-east. The area occupied by species showed two taxa that had a decreasing trend in spatial extent and one species that was expanding. The mean westward and contracting trends of the assemblage were interpreted as likely signals of climate forcing, whereas the eastward shift of three species may be linked to fishing impacts. A lack of knowledge of subsurface oceanographic changes in the region challenges interpretation of the distribution changes and is identified as a research priority. We recommend additional research regarding causal drivers of distribution shifts, specifically to attribute observed changes to climate, fishing, and inter-annual environmental variability. [ABSTRACT FROM AUTHOR]

• Condition is still seldom or poorly defined in marine ecological studies. • A critical review of methods and indicators for condition assessments is provided. • Five Indicator categories, which vary in terms of data requirements and inference. • This review supports indicator selection & framework development for assessments. This review provides a broad conceptual overview of different approaches to measuring marine ecosystem condition and guidance for framework development (particularly relevant for developing countries). The objectives were to review definitions of ecosystem condition and identify the core approaches and key challenges within the research area. Furthermore, we reviewed the advantages and disadvantages of different indicators that can be used for condition assessments. A semi-systematic approach drawing from more than 300 studies covering a broad range of methods was followed. Generally, definitions of ecosystem condition are based on known changes to the ecosystem, but ultimately, they should align with the definition of an ecosystem and consider ecosystem structure and functioning. As far as possible, the definition should relate an observed state to a reference condition or ecological target. Importantly, definitions of condition should be practical, scalable and always provided when conducting condition assessments. Five indicator categories were identified including pressures, physical parameters, biological structure, functional structure and ecological models. Indicators mostly focus on drivers of change (i.e. ex situ pressures) or the structure of the ecosystem, as these data are easier to obtain. While valuable, these classes of indicators can only provide an indirect appraisal of ecosystem functioning in instances where the relationship between pressure, structure and functioning are known. Indicators that measure structure and functioning of an ecosystem can be used to directly report on condition; however, the data (and monitoring) requirements make them impractical in most instances. Ideally, integrated assessments, that measure indicators from all indicator categories, should be prioritised to provide a comprehensive overview of condition. However, this often requires transdisciplinary collaboration, substantial research capacity (and associated funding) and time to collect the necessary data. An alternative is to select a few strategic indicators that can provide data to address the definition of ecosystem condition and at the same time provide a feasible approach to address the project specific research objectives. Where possible, a data-derived approach should be followed as in situ measurements have potential to improve the understanding of impacts of anthropogenic pressures on ecosystem functioning, and in turn facilitate better management of human activities and enhance ecosystem functioning. [ABSTRACT FROM AUTHOR]

One of the stated applications of the IUCN Red List of Ecosystems (RLE) is to influence government policy and decision-making. We share 15 years' experience in integrating an independently developed indicator of ecosystem threat status into government policies and practice. South Africa's ecosystem threat status indicator was conceptualised in the early 2000s and progressed from a project-based indicator to listing of threatened ecosystems in terms of national legislation in 2011. We show the range of applications of the indicator, from its use as a headline indicator in the National Biodiversity Assessment to its role as a direct trigger for Environmental Impact Assessment. The strong link between threatened ecosystems and systematic conservation planning in South Africa also enabled ecosystem threat status to inform multi-sectoral development planning and decision-making. We show how bridging products, data availability, persistent mainstreaming and stakeholder engagement have encouraged the use of the indicator in government policy. The advantages and disadvantages of legislative listing are shared. Sound scientific foundations, combined with pragmatism, have provided a policy-relevant tool for focussing management on threatened ecosystems. We make active recommendations that will facilitate the policy uptake of the IUCN RLE in other countries. [ABSTRACT FROM AUTHOR]