AN EVALUATION OF THE PERFORMANCE OF THE KOBE STRATEGY MATRIX: AN EXAMPLE BASED UPON A BIOMASS DYNAMIC ASSESSMENT MODEL

The main management objective of ICCAT is to maintain the populations of tuna and tuna-like fishes at levels which will permit the maximum sustainable catch. Scientific advice designed to meet this objective, in common with other tuna Regional Fisheries Management Organisations' (tRFMO) scientific committees is presented in the form of the Kobe II Strategy Matrix (K2SM). This is essentially a decision table showing the time taken to achieve management objectives (e.g., stock recovery) for different levels of TAC or effort. The role of the K2SM as an important tool to communicate efficiently among all stakeholders and to assist in the decision-making process according to different levels of risk has been recognised.JRC.G.4-Maritime affair

A KOBE STRATEGY MAATRIX BASED UPON PROBABILISTIC REFERENCE POINTS: AN EXAMPLE USING A BIOMASS DYNAMIC ASSESSMENT MODEL

The main management objective of ICCAT is to maintain the populations of tuna and tuna-like fishes at levels which will permit the maximum sustainable catch. Scientific advice designed to meet this objective, in common with other tuna Regional Fisheries Management Organisations (tRFMO) scientific committees, is presented in the form of the Kobe II Strategy Matrix (K2SM). A decision table is given showing the time taken to achieve management objectives (e.g., stock recovery) for different levels of TAC or effort. However, substantial uncertainties still remain in assessments and therefore a key area of research is to show how uncertainty and improvements in information, consistent with the principles of the precautionary approach, can be incorporated into advice, so that for any level of uncertainty there is the same risk of depletion.JRC.G.4-Maritime affair

Distribución estival y abundancia de la gran manta raya (Mobula mobular) en el mar Adriático: datos de base para un marco de gestión iterativo

The giant devil ray (Mobula mobular) is a poorly understood protected endemic species of the eastern Atlantic-Mediterranean region. However, to date there are no range-wide management actions in place. This paper provides the first overview of the summer distribution and abundance of this species and other Myliobatiformes within the Adriatic Sea based on an aerial survey. Although the survey´s primary targets were cetaceans and sea turtles, the study showed that it was possible to use the survey to monitor other species. Abundance estimates are derived using conventional distance sampling analysis. Giant devil rays were observed mainly in the central-southern Adriatic (88% of total sightings). A total of 1595 giant devil rays were estimated in the central-southern Adriatic Sea [coefficient of variation(CV)=25%, uncorrected estimate for perception and availability bias]. When corrected for availability bias the number of specimens was estimated at 3255 (CV=56%). Population growth rate was estimated using life history traits and a sensitivity analysis was conducted to evaluate the benefit of improving biological knowledge on this data-poor species. A power analysis showed that a long-term commitment to an aerial survey would be necessary to monitor population trends. Conservation implications and future work, including how the study could be used to conduct an ecological risk assessment are discussed.La manta raya gigante (Mobula mobular) es una especie endémica protegida poco conocida de la región del Atlántico oriental-Mediterráneo. Sin embargo hasta la fecha no hay acciones de gestión que cubran todo su rango. Este artículo proporciona la primera visión de conjunto de la distribución y abundancia estival de esta especie y otras Myliobatiformes en el mar Adriático basada en un censo aéreo. Aunque los objetivos principales del censo eran cetáceos y tortugas marinas, el estudio mostró que era posible usar el censo para monitorizar otras especies. Las estimas de abundancia se derivaron utilizando análisis convencional de muestreo de distancias. Las manta rayas gigantes se observaron principalmente en el Adriático central y sur (88% de los avistamientos totales). Se estimaron un total de 1595 mantas rayas gigantes en el mar Adriático central-sur (CV=25%, estima no corregida para los sesgos de percepción y de disponibilidad). Cuando se corrigió para el sesgo de disponibilidad el número de especímenes se estimó en 3255 (CV=56%). La tasa de crecimiento de la población se estimó usando aspectos de la historia natural y se realizó un análisis de sensibilidad para evaluar el beneficio de mejorar el conocimiento biológico de esta especie de la que hay tan pocos datos. Un análisis de potencia mostró que sería necesario un compromiso a largo plazo para realizar censos aéreos para monitorizar las tendencias de la población. Se discuten las implicaciones para la conservación y trabajo futuro, incluyendo cómo se podría utilizar este estudio para llevar a cabo una evaluación ecológica de riesgo

The Potential for Insurance to Mediate Economic Risks in Marine Fisheries

In agriculture there has been a long history of using a levy or an insurance premium to create mutual funds to mediate economic risks to growers due to environmental variability and quarantine pests. In the United States the federal government, through the USDA, continues to underwrite funds (collected by private insurance agents) which are used to protect contributors from the effects of extreme weather and pest and disease losses. In Europe mutual funds such as the Kartoffelafgiftsfonden in Denmark and Potatopol in the Netherlands have been developed to mediate risks from some potato diseases in different ways. This paper uses established methods of economic risk management from agriculture and applies these to marine fisheries to demonstrate how financial risks could be mediated by the creation of insurance funds. Through the use of probabilistic estimates of future catches and prices, and the risk of depletion across various scenarios, we investigate how government and industry participation in creating and managing funds may encourage increased protection of fisheries, and compliance and enforcement for fishery regulations. The paper also explores how fund exposure may be reduced by the application of reinsurance from commercial insurers for the upper tail of high cost, low probability events, such as total fishery collapse

On the role of visualisation in fisheries management

Environmental change has focused the attention of scientists, policy makers and the wider public on the uncertainty inherent in interactions between people and the environment. Governance in fisheries is required to involve stakeholder participation and to be more inclusive in its remit, which is no longer limited to ensuring a maximum sustainable yield from a single stock but considers species and habitat interactions, as well as social and economic issues. The increase in scope, complexity and awareness of uncertainty in fisheries management has brought methodological and institutional changes throughout the world. Progress towards comprehensive, explicit and participatory risk management in fisheries depends on effective communication. Graphic design and data visualisation have been underused in fisheries for communicating science to a wider range of stakeholders. In this paper, some of the general aspects of designing visualisations of modelling results are discussed and illustrated with examples from the EU funded MYFISH project. These infographics were tested in stakeholder workshops, and improved through feedback from that process. It is desirable to convey not just modelling results but a sense of how reliable various models are. A survey was developed to judge reliability of different components of fisheries modelling: the quality of data, the quality of knowledge, model validation efforts, and robustness to key uncertainties. The results of these surveys were visualized for ten different models, and presented alongside the main case study.Versión del editor1,86

Relevance for Economic and Biological Management Objectives of MSY-based Reference Points for Multispecies, Multifleet Fisheries: a North Sea Plaice and Sole Case Study

Maximum sustainable yield (MSY) has been recommended as a reference point for fisheries sustainability. However, like other reference points it is generally applied on a single-species basis. This has potentially significant biological implications in a complex multispecies fishery. MSY-based reference points also have economic implications for fisheries prosecuting the resource. To examine these issues, interactions between North Sea plaice (Pleuronectes platessa) and sole (Solea solea) stocks and two fishing fleets (northern and southern) will be modelled, incorporating changes in stock distribution, productivity and resilience. Fleet- and species-specific implications of a range of management objectives, including MSY, for fishery sustainability and profitability will be examined

Ten lessons on the resilience of the EU common fisheries policy towards climate change and fuel efficiency - A call for adaptive, flexible and wellinformed fisheries management

To effectively future-proof the management of the European Union fishing fleets we have explored a suite of case studies encompassing the northeast and tropical Atlantic, the Mediterranean, Baltic and Black Seas. This study shows that European Union (EU) fisheries are likely resilient to climate-driven short-term stresses, but may be negatively impacted by long-term trends in climate change. However, fisheries’ long-term stock resilience can be improved (and therefore be more resilient to increasing changes in climate) by adopting robust and adaptive fisheries management, provided such measures are based on sound scientific advice which includes uncertainty. Such management requires regular updates of biological reference points. Such updates will delineate safe biological limits for exploitation, providing both high long-term yields with reduced risk of stock collapse when affected by short-term stresses, and enhanced compliance with advice to avoid higher than intended fishing mortality. However, high resilience of the exploited ecosystem does not necessarily lead to the resilience of the economy of EU fisheries from suffering shocks associated with reduced yields, neither to a reduced carbon footprint if fuel use increases from lower stock abundances. Fuel consumption is impacted by stock development, but also by changes in vessel and gear technologies, as well as fishing techniques. In this respect, energy-efficient fishing technologies already exist within the EU, though implementing them would require improving the uptake of innovations and demonstrating to stakeholders the potential for both reduced fuel costs and increased catch rates. A transition towards reducing fuel consumption and costs would need to be supported by the setup of EU regulatory instruments. Overall, to effectively manage EU fisheries within a changing climate, flexible, adaptive, well-informed and well-enforced management is needed, with incentives provided for innovations and ocean literacy to cope with the changing conditions, while also reducing the dependency of the capture fishing industry on fossil fuels. To support such management, we provide 10 lessons to characterize ‘win-win’ fishing strategies for the European Union, which develop leverages in which fishing effort deployed corresponds to Maximum Sustainable Yield targets and Common Fisheries Policy minimal effects objectives. In these strategies, higher catch is obtained in the long run, less fuel is spent to attain the catch, and the fisheries have a higher resistance and resilience to shock and long-term factors to face climate-induced stressesEn prens

Limiting inter-annual variation in total allowable catch strategies. An application to ICES roundfish stocks

This study evaluated through simulation management strategy that stabilise catch levels by setting bounds on the inter-annual variability in Total Allowable Catches (TACs). An integrated modelling approach was used, which modelled both the ‘real’ and observed systems and the interactions between all system components. The modelling framework therefore allowed evaluation of the robustness of candidate management strategies to both the intrinsic properties of the systems, and the ability to observe, monitor, assess and control them. Strategies were evaluated in terms of level of risk (measured as the probability of spawning stock biomass falling below the biomass limit reference level for the stock) and cumulative yield. The simulation approach used provides a powerful tool for the examination of the performance of candidate management strategies. It has shown that better management is not necessarily going to be achieved by improving the assessement, since even with a perfect assessment (where the simulated working group knew stock status perfectly) stocks may crash at fishing levels that standard stochastic projections would suggest were safe. Also explicitly modelling the assessment process can result in quite different outcomes than those predicted by the simple projection traditionally used by stock assessment working groups. This is because the simple projection assumes that the status of the stock in the current year is known without error and that the target fishing mortality can be achieved without error. However, in practice the assessment is based on last years data and the effect of any management measure on SSB is only manifest, following the implementation of the quota, at the end of the following year. The choice of target and fishing mortality levels and minimum stock levels results from ICES interpretation of the precautionary approach. This lead to the definition of fishing mortality and biomass reference points that are intended to prevent over-fishing and to trigger recovery plans when a stock is overfished respectively. Although, fishing mortality and biomass reference points were originally intended to be independent, a fishing mortality level implies a corresponding biomass level. In the case of saithe a fishing mortality of 0.40 (i.e. the FPA level) would drive the stock to Blim, suggesting that the choice of biomass and target reference points are not consistent for this stock

Limiting inter-annual variation in total allowable catch strategies. An application to ICES roundfish stocks

This study evaluated through simulation management strategy that stabilise catch levels by setting bounds on the inter-annual variability in Total Allowable Catches (TACs). An integrated modelling approach was used, which modelled both the ‘real’ and observed systems and the interactions between all system components. The modelling framework therefore allowed evaluation of the robustness of candidate management strategies to both the intrinsic properties of the systems, and the ability to observe, monitor, assess and control them. Strategies were evaluated in terms of level of risk (measured as the probability of spawning stock biomass falling below the biomass limit reference level for the stock) and cumulative yield. The simulation approach used provides a powerful tool for the examination of the performance of candidate management strategies. It has shown that better management is not necessarily going to be achieved by improving the assessement, since even with a perfect assessment (where the simulated working group knew stock status perfectly) stocks may crash at fishing levels that standard stochastic projections would suggest were safe. Also explicitly modelling the assessment process can result in quite different outcomes than those predicted by the simple projection traditionally used by stock assessment working groups. This is because the simple projection assumes that the status of the stock in the current year is known without error and that the target fishing mortality can be achieved without error. However, in practice the assessment is based on last years data and the effect of any management measure on SSB is only manifest, following the implementation of the quota, at the end of the following year. The choice of target and fishing mortality levels and minimum stock levels results from ICES interpretation of the precautionary approach. This lead to the definition of fishing mortality and biomass reference points that are intended to prevent over-fishing and to trigger recovery plans when a stock is overfished respectively. Although, fishing mortality and biomass reference points were originally intended to be independent, a fishing mortality level implies a corresponding biomass level. In the case of saithe a fishing mortality of 0.40 (i.e. the FPA level) would drive the stock to Blim, suggesting that the choice of biomass and target reference points are not consistent for this stock