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Global biodiversity and ecosystem service models typically operate independently. Ecosystem service projections may therefore be overly optimistic because they do not always account for the role of biodiversity in maintaining ecological functions. We review models used in recent global model intercomparison projects and develop a novel model integration framework to more fully account for the role of biodiversity in ecosystem function, a key gap for linking biodiversity changes to ecosystem services. We propose two integration pathways. The first uses empirical data on biodiversity–ecosystem function relationships to bridge biodiversity and ecosystem function models and could currently be implemented globally for systems and taxa with sufficient data. We also propose a trait-based approach involving greater incorporation of biodiversity into ecosystem function models. Pursuing both approaches will provide greater insight into biodiversity and ecosystem services projections. Integrating biodiversity, ecosystem function, and ecosystem service modeling will enhance policy development to meet global sustainability goals.

We describe the design and implementation of lessons in undergraduate abstract algebra that integrate applications to teaching high school mathematics. Each lesson consists of a pre-activity, class...

This paper introduces lessons designed to incorporate applications to teaching high school mathematics in an undergraduate Discrete Mathematics course. Because many prospective high school teachers...

The availability of colonizable substrate is an important driver of the temporal dynamics of sessile invertebrates on coral reefs. Increased dominance of algae and, in some cases, sponges has been documented on many coral reefs around the world, but how these organisms benefit from non-colonized substrate on the reef is unclear. In this study, we described the temporal dynamics of benthic organisms on an Indonesian coral reef across two time periods between 2006 and 2017 (2006–2008 and 2014–2017), and investigated the effects of colonizable substrate on benthic cover of coral reef organisms at subsequent sampling events. In contrast with other Indonesian reefs where corals have been declining, corals were dominant and stable over time at this location (mean ± SE percentage cover 42.7 ± 1.9%). Percentage cover of turf algae and sponges showed larger interannual variability than corals and crustose coralline algae (CCA) (P < 0.001), indicating that these groups are more dynamic over short temporal scales. Bare substrate was a good predictor of turf cover in the following year (mean effect 0.2, 95% CI: 0–0.4). Algal cover combined with bare space was a good predictor of CCA cover the following year generally, and of sponge cover the following year but only at one of the three sites. These results indicate that turf algae on some Indonesian reefs can rapidly occupy free space when this becomes available, and that other benthic groups are probably not limited by the availability of bare substrate, but may overgrow already fouled substrates.

The rate of change in marine ecosystems and the speed with which pressure on those systems is escalating are much faster than rates of institutional change or management responses. The continued promulgation of a century‐old management approach (i.e., single species maximum sustainable yield), despite decades of scientific warnings regarding its flaws, highlights how fisheries management and science can be constrained by path dependency and psychological traps. Major disruptions to the functioning of fisheries created by climate and SARS‐CoV‐2 (COVID‐19) present an opportunity to take a step back and introduce alternative approaches more appropriate to the extant conditions in the majority of global fisheries. This reset point, in combination with a proliferation of cheaper technological options, provides the opportunity for fisheries in emerging economies to reach a sustainable position without retracing the steps, or holding to the assumptions behind the fisheries management approaches applied in regions such as Europe, North America or Australia.

The ocean economy is experiencing rapid growth that will provide benefits but will also pose environmental and social risks. With limited space and degraded resources in coastal areas, offshore waters will be a particular focus of Blue Economy expansion over the next decade. When emerging and established economic sectors expand in offshore waters (within national Exclusive Economic Zones), different potential Blue Economy opportunities and challenges will arise. Following a series of interdisciplinary workshops, we imagine two technically possible futures for the offshore Blue Economy and we identify the actions required to achieve the more sustainable outcome. Under a business as usual scenario the focus will remain on economic growth, the commodification of nature, the dominance of private over public and cultural interests, and prioritisation of the interests of current over future generations. A more sustainable scenario would meet multiple UN Sustainable Development Goals and ensure inclusive economic developments, environmental sustainability, and fair and equitable access to resources and technologies across users, nations, and generations. Challenges to this more sustainable future are a lack of infrastructure and technology to support emerging offshore sectors, limited understanding of environmental impacts, inequitable outcomes, and a lack of planning and governmental oversight. Addressing these challenges will require a shift in societal values, a more balanced allocation of funding to offshore activities, transparency in information sharing between industries and across nations, and adjustment of international legal and institutional mechanisms. The sustainable and equitable offshore Blue Economy we envisage is achievable and provides a unique opportunity to build global capacity and partnership. Graphic abstract Electronic supplementary material The online version of this article (10.1007/s11160-020-09628-6) contains supplementary material, which is available to authorized users.

Transfer efficiency is the proportion of energy passed between nodes in food webs. It is an emergent, unitless property that is difficult to measure, and responds dynamically to environmental and ecosystem changes. Because the consequences of changes in transfer efficiency compound through ecosystems, slight variations can have large effects on food availability for top predators. Here, we review the processes controlling transfer efficiency, approaches to estimate it, and known variations across ocean biomes. Both process-level analysis and observed macroscale variations suggest that ecosystem-scale transfer efficiency is highly variable, impacted by fishing, and will decline with climate change. It is important that we more fully resolve the processes controlling transfer efficiency in models to effectively anticipate changes in marine ecosystems and fisheries resources.

At the global scale, biodiversity indicators are typically used to monitor general trends, but are rarely implemented with specific purpose or linked directly to decision making. Some indicators are better suited to predicting future change, others are more appropriate for evaluating past actions, but this is seldom made explicit. We developed a conceptual model for assigning biodiversity indicators to appropriate functions based on a common approach used in economics. Using the model, indicators can be classified as leading (indicators that change before the subject of interest, informing preventative actions), coincident (indicators that measure the subject of interest), or lagging (indicators that change after the subject of interest has changed and thus can be used to evaluate past actions). We classified indicators based on ecological theory on biodiversity response times and management objectives in 2 case studies: global species extinction and marine ecosystem collapse. For global species extinctions, indicators of abundance (e.g., the Living Planet Index or biodiversity intactness index) were most likely to respond first, as leading indicators that inform preventative action, while extinction indicators were expected to respond slowly, acting as lagging indicators flagging the need for evaluation. For marine ecosystem collapse, indicators of direct responses to fishing were expected to be leading, while those measuring ecosystem collapse could be lagging. Classification defines an active role for indicators within the policy cycle, creates an explicit link to preventative decision-making, and supports preventative action.Alineamiento entre los Indicadores de Biodiversidad y los Requerimientos Políticos Resumen En la escala global, los indicadores de biodiversidad se usan comúnmente para monitorear las tendencias generales pero rara vez se implementan con un propósito específico o vinculados directamente con la toma de decisiones. Algunos indicadores son mejores para predecir los cambios futuros, mientras que otros son más apropiados para la evaluación de acciones pasadas, aunque lo anterior casi nunca se comunica explícitamente. Desarrollamos un modelo conceptual para la atribución de indicadores de biodiversidad a funciones apropiadas con base en una estrategia común que se usa en la economía. Con este modelo, los indicadores pueden clasificarse como principales (indicadores que cambian antes que el sujeto de interés, orientando así las acciones preventivas), coincidentes (indicadores que miden al sujeto de interés) o rezagados (indicadores que cambian después de que el sujeto de interés ha cambiado y por lo tanto puede usarse para evaluar las acciones pasadas). Clasificamos los indicadores con base en la teoría ecológica sobre los tiempos de respuesta de la biodiversidad y los objetivos de manejo en dos estudios de caso: la extinción mundial de especies y el colapso de los ecosistemas marinos. Para la extinción mundial de especies, los indicadores de abundancia (p. ej.: el Índice del Planeta Viviente o el índice de biodiversidad intacta) fueron los más probables en tener una respuesta pronta como indicadores principales que orientan las acciones preventivas, mientras que se esperó que los indicadores de extinción tuvieran respuestas lentas, por lo que actuarían como indicadores rezagados que disminuyeron la necesidad de evaluación. Para el colapso de los ecosistemas marinos, se anticipó que los indicadores de las respuestas directas a la pesca fueran los indicadores principales, mientras que aquellos que miden el colapso del ecosistema podrían ser indicadores rezagados. La clasificación define un papel activo para los indicadores dentro del ciclo de políticas, crea un vínculo explícito con la toma de decisiones preventivas y respalda la acción preventiva.在全球范围内, 生物多样性指标常常用于监测整体趋势, 但很少有具体实施目的或直接与决策挂钩。有些指标更适合预测未来的变化, 有些指标则更适合评价过去的行动, 但这一点很少得到说明。基于经济学中的常用方法, 我们开发了一个根据恰当功能分配生物多样性指标的概念模型。该模型将指标分为领先指标 (先于研究主体发生变化的指标, 可为预防性行动提供信息) 、同步指标 (度量研究主体的指标) 及滞后指标 (研究主体变化后才发生变化的指标, 可用于评估过去的行动) 。我们以全球物种灭绝和海洋生态系统崩溃作为案例, 根据生物多样性响应时间的生态学理论和管理目标对相应指标进行了分类。在全球物种灭绝的案例中, 种群数量指标 (如地球生命力指数或生物多样性完整性指数) 最有可能首先产生响应, 它们是可以为预防行动提供信息的领先指标, 而灭绝相关的指标预期响应缓慢, 则是表明评估需求的滞后指标。对于海洋生态系统崩溃而言, 衡量对渔业直接响应的指标应为领先指标, 而生态系统崩溃的相关指标可能为滞后指标。对指标的分类确定了其在政策周期中的积极作用, 建立了指标与预防性决策的明确联系, 并支持了预防性行动。【翻译: 胡怡思; 审校: 聂永刚】.

Fishing is a strong selective force and is supposed to select for earlier maturation at smaller body size. However, the extent to which fishing‐induced evolution is shaping ecosystems remains debated. This is in part because it is challenging to disentangle fishing from other selective forces (e.g., size‐structured predation and cannibalism) in complex ecosystems undergoing rapid change.Changes in maturation size from fishing and predation have previously been explored with multi‐species physiologically structured models but assumed separation of ecological and evolutionary timescales. To assess the eco‐evolutionary impact of fishing and predation at the same timescale, we developed a stochastic physiologically size‐structured food‐web model, where new phenotypes are introduced randomly through time enabling dynamic simulation of species' relative maturation sizes under different types of selection pressures.Using the model, we carried out a fully factorial in silico experiment to assess how maturation size would change in the absence and presence of both fishing and predation (including cannibalism). We carried out ten replicate stochastic simulations exposed to all combinations of fishing and predation in a model community of nine interacting fish species ranging in their maximum sizes from 10 g to 100 kg. We visualized and statistically analyzed the results using linear models.The effects of fishing on maturation size depended on whether or not predation was enabled and differed substantially across species. Fishing consistently reduced the maturation sizes of two largest species whether or not predation was enabled and this decrease was seen even at low fishing intensities (F = 0.2 per year). In contrast, the maturation sizes of the three smallest species evolved to become smaller through time but this happened regardless of the levels of predation or fishing. For the four medium‐size species, the effect of fishing was highly variable with more species showing significant and larger fishing effects in the presence of predation.Ultimately our results suggest that the interactive effects of predation and fishing can have marked effects on species' maturation sizes, but that, at least for the largest species, predation does not counterbalance the evolutionary effect of fishing. Our model also produced relative maturation sizes that are broadly consistent with empirical estimates for many fish species., Fishing is a strong evolutionary force, but its interplay with predation remains unclear. Using a community size‐spectrum model we show that fishing has strongest evolutionary effect on large predatory species, but minor impact on small species. Middle‐sized species are sandwiched between fishing and predation and their responses are highly variable.

To describe the severity and clinical spectrum of coronavirus disease 2019 (COVID-19) in children during the 2021 New South Wales outbreak of the Delta variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).Prospective cohort study in three metropolitan Sydney local health districts, 1 June - 31 October 2021.Children under 16 years of age with positive SARS-CoV-2 nucleic acid test results admitted to hospital or managed by the Sydney Children's Hospital Network (SCHN) virtual care team.Age-specific SARS-CoV-2 infection frequency, overall and separately for SCHN virtual and hospital patients; rates of medical and social reason admissions, intensive care admissions, and paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 per 100 SARS-CoV-2 infections; demographic and clinical factors that influenced likelihood of hospital admission.A total of 17 474 SARS-CoV-2 infections in children under 16 were recorded in NSW, of whom 11 985 (68.6%) received SCHN-coordinated care, including 459 admitted to SCHN hospitals: 165 for medical reasons (1.38 [95% CI, 1.17-1.59] per 100 infections), including 15 admitted to intensive care, and 294 (under 18 years of age) for social reasons (2.45 [95% CI, 2.18-2.73] per 100 infections). In an analysis that included all children admitted to hospital and a random sample of those managed by the virtual team, having another medical condition (adjusted odds ratio [aOR], 7.42; 95% CI, 3.08-19.3) was associated with increased likelihood of medical admission; in univariate analyses, non-asthmatic chronic respiratory disease was associated with greater (OR, 9.21; 95% CI, 1.61-174) and asthma/viral induced wheeze with lower likelihood of admission (OR, 0.38; 95% CI, 0.18-0.78). The likelihood of admission for medical reasons declined from infancy to 5-11 years, but rose again for those aged 12-15 years. Sex and Indigenous status did not influence the likelihood of admission.Most SARS-CoV-2 infections (Delta variant) in children were asymptomatic or associated with mild disease. Hospitalisation was relatively infrequent, and most common for infants, adolescents, and children with other medical conditions. More children were hospitalised for social than for medical reasons.

Summary In a rapidly changing world, scientists and research institutions need to plan for the infrastructure, skills, and policy engagement that will help society navigate social-ecological challenges. Foresighting draws on approaches used in strategic and long-range (>10 years) planning and participatory futures studies. Here, we describe a new quantitative approach to develop and rank 14 foresight scenarios across a range of general and marine-relevant science domains. Indicators for each foresight were used to assess the time-specific probability of each scenario being realized. Assessments by scientists in 2 consecutive years showed foresight scoring consistency and revealed surprises. Despite high variation among scientists in scoring the year that each indicator would occur, there was overall consistency across the foresights between years. We show that foresighting can be quantitative and that individual performance and changes in likelihood can be evaluated. This approach can motivate and guide strategic planning and investment decisions by scientific institutions in response to different anticipated futures and build skills in futures thinking.

Applied ecology has traditionally approached management problems through a simplified, single-species lens. Repeated failures of single-species management have led us to a new paradigm - managing at the ecosystem level. Ecosystem management involves a complex array of interacting organisms, processes and scientific disciplines. Accounting for interactions, feedback loops and dependencies between ecosystem components is therefore fundamental to understanding and managing ecosystems. We provide an overview of the main types of ecosystem models and their uses, and discuss challenges related to modelling complex ecological systems. Existing modelling approaches typically attempt to do one or more of the following: describe and disentangle ecosystem components and interactions; make predictions about future ecosystem states; and inform decision making by comparing alternative strategies and identifying important uncertainties. Modelling ecosystems is challenging, particularly when balancing the desire to represent many components of an ecosystem with the limitations of available data and the modelling objective. Explicitly considering different forms of uncertainty is therefore a primary concern. We provide some recommended strategies (such as ensemble ecosystem models and multi-model approaches) to aid the explicit consideration of uncertainty while also meeting the challenges of modelling ecosystems.

Marine ecosystem management is increasingly expected to take into account a wide range of ecological and socio‐economic factors. Decision‐making is helped by end‐to‐end ecosystem models that allow exploration of alternative management scenarios given a complex range of interacting factors. We present Atlantis – a spatially structured largely deterministic end‐to‐end marine ecosystem model written in C, available for all major operating systems, based on dynamically interacting physics, biology, fisheries, management, assessment and economics submodels. A detailed installation guide and example application files are also provided. One of the main features of Atlantis is its modularity. At the simplest level Atlantis can have uniform forcing of oceanographic processes, a single primary producer and a consumer. At the most complex level, Atlantis can be used with a range of environmentally driven ecological responses, complex and habitat‐dependent food web, dynamic assessment, management and fishing effort driven by market forces and human behaviour. The combination chosen should be guided by the available data and the questions to be answered. Atlantis provides a large and customizable list of output files and summary statistics that can be analysed and plotted using a number of dedicated r packages. When applying the Atlantis package, the users should be aware of the caveats associated with complex models, such as parameter and structural model uncertainty and challenges interpreting interactions of multiple processes.

Despite frequent calls for Integrated Management (IM) of coastal and marine activities, there is no consensus on the ‘recipe’ for successful adoption and implementation, and there has been insufficient evaluation of successes and failures of IM to date. The primary rationale for IM is to overcome four major deficiencies of sector-based management: a) management of diverse activities by different agencies using different approaches, b) management generally focused on a subset of primarily ecological objectives that do not properly articulate or evaluate social, cultural, economic and institutional objectives, c) no mechanisms to evaluate or advise on trade-offs among objectives of activities in relation to objectives and d) no mechanisms to evaluate the cumulative effects of all managed activities. To help overcome this gap in knowledge, here we draw on our collective experiences working in Australia and Canada to develop and articulate a framework to help guide the practical implementation and evaluation of IM, which we define as: ‘An approach that links (integrates) planning, decision-making and management arrangements across sectors in a unified framework, to enable a more comprehensive view of sustainability and the consideration of cumulative effects and trade-offs.’ We argue that IM will be most easily and effectively achieved by linking and modifying existing sector-based plans in an overarching IM initiative that has nine key features: 1) Recognition of need for IM, 2) A shared vision by stakeholders and decision-makers for IM, 3) Appropriate legal and institutional frameworks for coordinated decision-making, 4) Sufficient and effective processes for stakeholder engagement and participation, 5) A common and comprehensive set of operational objectives, 6) Explicit consideration of trade-offs and cumulative impacts, 7) Flexibility to adapt to changing conditions, 8) Processes for ongoing review and refinement, and 9) Effective resourcing, capacity, leadership and tools. Drawing on these features we then articulate a process for the implementation and evaluation of IM that recognises five phases: i) Preconditions and drivers of change, ii) Intentional design and institutional rearrangement, iii) Enablers and disablers iv) An implemented IM process, and v) Review of IM performance and modification. Combination of the nine features of IM with the five phases in IM development provides a framework for implementation and a lens for evaluation of IM processes. We suggest that this framework provides a guide to the appropriate design of practical IM, which will assist in overcoming the current management deficiencies and improve the sustainability of marine resources in the face of change.

Natural communities can undergo large temporal changes in abundance and species composition that may be difficult to detect without long-term ecological monitoring. Characterizing temporal variability in coral reef fauna is critical for predicting how reef ecosystems will be impacted by environmental change. Sponges are an ecologically important component of coral reefs, yet descriptions of temporal dynamics of multi-species sponge assemblages are scarce. We studied temporal changes in abundance and biodiversity of an Indonesian coral reef sponge assemblage over 13 yr (2005−2017). Mean (±SE) sponge abundance (sponge patches m) initially increased from 124.06 ± 8.46 to 183.73 ± 12.12 in 2005−2007 (p < 0.001), declined to 66.53 ± 10.62 in 2007−2014 (p < 0.001), and increased to 105.87 ± 15.42 in 2014−2017 (p < 0.001). These patterns in sponge abundance did not depend on water temperature. Overall, we recorded 141 sponge taxa. However, species composition showed strong temporal patterns driven by a few abundant taxa (e.g. Protosuberites sp., Sycon sp., and Pericharax sp., respectively accounting on average for ~25, 20, and 5% of total sponge abundance). Species richness increased with sponge abundance (p < 0.001), whereas evenness decreased due to dominance of some taxa in years of high sponge abundance (p = 0.002). Our study highlights that the abundance and biodiversity of Indo-Pacific sponge assemblages undergo dramatic temporal changes driven by species-specific population variability. This variability has important implications for designing monitoring programs, for interpreting experimental studies, and for understanding long-term responses of coral reefs to perturbations.

Previous reconstructions of marine fishing fleets have aggregated data without regard to the artisanal and industrial sectors. Engine power has often been estimated from subsets of the developed world, leading to inflated results. We disaggregated data into three sectors, artisanal (unpowered/powered) and industrial, and reconstructed the evolution of the fleet and its fishing effort. We found that the global fishing fleet doubled between 1950 and 2015—from 1.7 to 3.7 million vessels. This has been driven by substantial expansion of the motorized fleet, particularly, of the powered-artisanal fleet. By 2015, 68% of the global fishing fleet was motorized. Although the global fleet is dominated by small powered vessels under 50 kW, they contribute only 27% of the global engine power, which has increased from 25 to 145 GW (combined powered-artisanal and industrial fleets). Alongside an expansion of the fleets, the effective catch per unit of effort (CPUE) has consistently decreased since 1950, showing the increasing pressure of fisheries on ocean resources. The effective CPUE of most countries in 2015 was a fifth of its 1950s value, which was compared with a global decline in abundance. There are signs, however, of stabilization and more effective management in recent years, with a reduction in fleet sizes in developed countries. Based on historical patterns and allowing for the slowing rate of expansion, 1 million more motorized vessels could join the global fleet by midcentury as developing countries continue to transition away from subsistence fisheries, challenging sustainable use of fisheries' resources.

This article recognizes that the impacts and effects of fishing are key to marine ecosystem management and explores the relationship between fisheries exploitation and sustainable harvests, and the collapse and depletion of stocks. A survey of 21 fisheries from around the world assessed key biological, environmental, social, economic, industry, governance, and management variables and associated criteria that potentially affect stock abundance. We developed 51 criteria as potential contributing factors underpinning three main fishery management outcomes: a sustainable fishery, a depleted fishery, or a collapsed fishery. The criteria that scored highest for the 15 sustainable fisheries in the analysis were associated with the broad groupings of biology (characteristics of the species and stock), management (legal and policy frameworks, tools and decision systems), and industry (economic performance and value). This analysis showed that while a fishery might have a high score for management, sustainability is likely to be difficult to achieve without a medium or high score for biological knowledge.

Cephalopods, especially squids, are believed to have a structuring role in marine ecosystems as a link between different trophic levels, primarily due to their voracious prey consumption and high production rate. Cephalopod ecology, however, is still poorly understood as observational studies often give highly uncertain and variable results due to the peculiarities of cephalopod behaviour and biology, and their responsiveness to external drivers. This review evaluates our representation of cephalopods in ecosystem models and the insights given by these models on the role of cephalopods in our oceans. We examined ecosystem models from 13 regions to analyse the representation of cephalopods and compared their results to local trophic studies. Our analysis indicated that most ecosystem models inadequately include cephalopods in terms of model structure and parametrization; although some models still have the capacity to draw valuable conclusions regarding the impact and role of cephalopods within the system. Oceanic squid species have a major role linking trophic levels and food webs from different habitats. The importance of neritic species varies locally, but generally cephalopods have a substantial impact via their consumer role. To better understand the ecological role of cephalopods, improved representation of these species in ecosystem models is a critical requirement and could be achieved relatively easily to more accurately articulate the mechanisms regulating the ecological role of cephalopods.

Use those multicolored linking bricks to help students connect measurement with an understanding of number and operations as well as fractions.

As atmospheric CO2 levels continue to rise so too does the risk of severe impacts. Scientists clearly have an important role to play in preparing for and responding to climate change impacts; however, calls by scientists for global action have not led to the required changes. It is timely, therefore, for scientists to critically consider their own approach toward climate change research, particularly if we are to ameliorate or adapt to unwanted outcomes. Here we present three different pathways that allow scientists and scientific institutions to conceptualize the implications of their responses to climate change scenarios. These pathways are illustrated via three plausible futures for the marine environment under climate change. This approach allows future responsibilities, outcomes, and implication to be explored within and across pathways and can be applied to different scenarios for scientists and scientific institutions to anticipate and better prepare to contribute effectively to the future.

Marine ecosystem models that incorporate fisheries and climate change are essential for forecasting and guiding sustainable ecosystem management decisions. A key challenge in developing and applying ecosystem models that are able to provide robust predictions for management is to accurately represent the structure and dynamics of food webs. Ecosystem models vary in complexity and formulation and there is no set method routinely used to evaluate the skill of a model to correctly represent food web characteristics. One approach for evaluation is the comparison of modelled food web attributes with measures of stable isotope composition of taxa. While this approach has been used in some studies, its full potential has not been realised. Critically, directly modelling the assumed underlying processes that give rise to stable isotope signatures in ecosystem models has only just begun to be explored. Here, we examine the process of building ecosystem models and assess the potential for incorporating stable isotope results into this process, including the evaluation of model skill. We consider both size- and species- based ecosystem modelling approaches for their potential in this regard. We discuss that whilst conceptually achievable, in practice this is highly challenging through highlighting the advances and challenges in using stable isotope data, including the implications of precision associated with isotope-based measurements. We conclude with a proposed framework for explicitly integrating stable isotope data into both size- and species- based ecosystem models as an example of how signatures may be more powerfully used in the modelling process, and highlight key needs for future work.

Ecological indicators used to monitor fishing effects in the context of climate change and variability need to be informative to enable effective ecosystem-based fisheries management. We evaluated the specificity of the response of ecosystem indicators to different fishing and environmental pressure levels using Ecosim and Atlantis ecosystem models for the southern Benguela ecosystem. Three fishing strategies were modelled to represent a variety of ways of targeting fishing within an ecosystem: one focused on low trophic levels (i.e. forage species), another on higher trophic levels (i.e. predatory fish) and a third tested fishing pressure across the full range of potentially exploitable species. Two types of environmental change were simulated for each fishing mortality scenario – random environmental variability and directional climate change. The specificity of selected ecological indicators (mean trophic level of the community, proportion of predatory fish, biomass/landings, mean intrinsic vulnerability and marine trophic index) was evaluated for different combinations of fishing strategy, fishing mortality and both types of environmental change. While there were mostly large differences in indicator values computed from the Atlantis and Ecosim models, the specificity of the ecological indicators considered under changing climate generally corresponded between the two models. Certain indicators (i.e. mean trophic level of the community) were less specific in detecting effects of fishing in the southern Benguela for some of the three fishing strategies modelled (i.e. high trophic level fishing strategy) under climate change. This helped refine the most appropriate indicator set for our system, reflecting the focus of a particular fishing strategy, and improved confidence in the suitability of these indicators for monitoring fishing effects in the Southern Benguela.