Overlooked impacts and challenges of the new European discard ban

Discards are the portion of animal and plant material in the catch that is dumped back at sea. The Common Fisheries Policy plan proposed by the European Commission for 2014-2020 presents a controversial goal: to enforce the landing of fishing discards as a measure to encourage their reduction. This historical and political decision will shape the future of the fishing exploitation in European Seas. Discards generated by European fleets are not negligible, and its reduction is an ecological, socioeconomical and moral imperative. However, it must be achieved through the reduction in discards at source and the promotion of selective and non-destructive gears. We argue it is doubtful that this discard ban will result in an effective reduction of discards. The proposed measure may, in fact, negatively affect ecosystems at all levels of biological hierarchy by disregarding the Ecosystem-Based Approach to Fisheries and the Precautionary Principle. It could negatively impact several species by increasing fishing mortality, also commercial species if discards are not accounted in the total allowable catch. Communities preying on discards will likely be affected. The role discards currently play in the energy turnover of current ecosystems will be modified and should be fully evaluated. The landing of discards will likely generate new markets of fishmeal due to the growing demands for marine living resources. The ban will require substantial public investment to deal with technical problems on board and to control and enforce. Therefore, this measure should be only implemented after rigorous scientific and technical studies have been developed

The impact of subsidies on the ecological sustainability and future profits from North Sea fisheries

Background: This study examines the impact of subsidies on the profitability and ecological stability of the North Sea fisheries over the past 20 years. It shows the negative impact that subsidies can have on both the biomass of important fish species and the possible profit from fisheries. The study includes subsidies in an ecosystem model of the North Sea and examines the possible effects of eliminating fishery subsidies.Methodology/Principal Findings: Hindcast analysis between 1991 and 2003 indicates that subsidies reduced the profitability of the fishery even though gross revenue might have been high for specific fisheries sectors. Simulations seeking to maximise the total revenue between 2004 and 2010 suggest that this can be achieved by increasing the effort of Nephrops trawlers, beam trawlers, and the pelagic trawl-and-seine fleet, while reducing the effort of demersal trawlers. Simulations show that ecological stability can be realised by reducing the effort of the beam trawlers, Nephrops trawlers, pelagic- and demersal trawl-and-seine fleets. This analysis also shows that when subsidies are included, effort will always be higher for all fleets, because it effectively reduces the cost of fishing.Conclusions/Significance: The study found that while removing subsidies might reduce the total catch and revenue, it increases the overall profitability of the fishery and the total biomass of commercially important species. For example, cod, haddock, herring and plaice biomass increased over the simulation when optimising for profit, and when optimising for ecological stability, the biomass for cod, plaice and sole also increased. When subsidies are eliminated, the study shows that rather than forcing those involved in the fishery into the red, fisheries become more profitable, despite a decrease in total revenue due to a loss of subsidies from the government

Understanding the structure and functioning of polar pelagic ecosystems to predict the impacts of change

The determinants of the structure, functioning and resilience of pelagic ecosystems across most of the polar regions are not well known. Improved understanding is essential for assessing the value of biodiversity and predicting the effects of change (including in biodiversity) on these ecosystems and the services they maintain. Here we focus on the trophic interactions that underpin ecosystem structure, developing comparative analyses of how polar pelagic food webs vary in relation to the environment. We highlight that there is not a singular, generic Arctic or Antarctic pelagic food web, and, although there are characteristic pathways of energy flow dominated by a small number of species, alternative routes are important for maintaining energy transfer and resilience. These more complex routes cannot, however, provide the same rate of energy flow to highest trophic-level species. Food-web structure may be similar in different regions, but the individual species that dominate mid-trophic levels vary across polar regions. The characteristics (traits) of these species are also different and these differences influence a range of food-web processes. Low functional redundancy at key trophic levels makes these ecosystems particularly sensitive to change. To develop models for projecting responses of polar ecosystems to future environmental change, we propose a conceptual framework that links the life histories of pelagic species and the structure of polar food webs

Valuing marine ecosystems: taking into account the value of ecosystem benefits in the Blue Economy

This publication highlights current thinking in ecosystem service valuation for the marine environment. Valuation of the direct and indirect benefits (for either societal welfare, healthand economic activities) stemming from marine ecosystem services, can help to assess the long-term sustainability of blue growth, support policy development and marinemanagement decisions, and raise awareness of the importance of the marine environment to society and in the economy. Recommendations are made on how to incorporate outputsfrom valuation studies into the traditional analyses used in resource and environmental economics and into the European marine policy landscape and related management anddecision making choices

A general framework for combining ecosystem models

When making predictions about ecosystems, we often have available a number of different ecosystem models that attempt to represent their dynamics in a detailed mechanistic way. Each of these can be used as a simulator of large-scale experiments and make projections about the fate of ecosystems under different scenarios to support the development of appropriate management strategies. However, structural differences, systematic discrepancies and uncertainties lead to different models giving different predictions. This is further complicated by the fact that the models may not be run with the same functional groups, spatial structure or time scale. Rather than simply trying to select a “best” model, or taking some weighted average, it is important to exploit the strengths of each of the models, while learning from the differences between them. To achieve this, we construct a flexible statistical model of the relationships between a collection of mechanistic models and their biases, allowing for structural and parameter uncertainty and for different ways of representing reality. Using this statistical meta-model, we can combine prior beliefs, model estimates and direct observations using Bayesian methods and make coherent predictions of future outcomes under different scenarios with robust measures of uncertainty. In this study, we take a diverse ensemble of existing North Sea ecosystem models and demonstrate the utility of our framework by applying it to answer the question what would have happened to demersal fish if fishing was to stop

A proposition for the diagnosis and treatment of gastro-oesophageal reflux disease in children: A report from a working group on gastro-oesophageal reflux disease

In this paper, a Working Group on Gastro-Oesophageal Reflux discusses recommendations for the first line diagnostic and therapeutic approach of gastro-oesophageal reflux disease in infants and children. All members of the Working Group agreed that infants with uncomplicated gastro-oesophageal reflux can be safely treated before performing (expensive and often unnecessary) complementary investigations. However, the latter are mandatory if symptoms persist despite appropriate treatment. Oesophageal pH monitoring of long duration (18-24 h) is recommended as the investigation technique of choice in infants and children with atypical presentations of gastro-oesophageal reflux. Upper gastro-intestinal endoscopy in a specialised centre is the technique of choice in infants and children presenting with symptoms suggestive of peptic oesophagitis. Prokinetics, still a relatively new drug family, have already obtained a definitive place in the treatment of gastro-oesophageal reflux disease in infants and children, especially if "non-drug" treatment (positional therapy, dietary recommendations, etc.) was unsuccessful. It was the aim of the Working Group to help the paediatrician with this consensus statement and guide-lines to establish a standardised management of gastro-oesophageal reflux disease in infants and children

Ecological indicators to capture the effects of fishing on biodiversityand conservation status of marine ecosystems

IndiSeas (“Indicators for the Seas”) is a collaborative international working group that was established in2005 to evaluate the status of exploited marine ecosystems using a suite of indicators in a comparative framework. An initial shortlist of seven ecological indicators was selected to quantify the effects of fishing on the broader ecosystem using several criteria (i.e., ecological meaning, sensitivity to fishing, data avail-ability, management objectives and public awareness). The suite comprised: (i) the inverse coefficient of variation of total biomass of surveyed species, (ii) mean fish length in the surveyed community, (iii)mean maximum life span of surveyed fish species, (iv) proportion of predatory fish in the surveyed community, (v) proportion of under and moderately exploited stocks, (vi) total biomass of surveyed species,and (vii) mean trophic level of the landed catch. In line with the Nagoya Strategic Plan of the Convention on Biological Diversity (2011–2020), we extended this suite to emphasize the broader biodiversity and conservation risks in exploited marine ecosystems. We selected a subset of indicators from a list of empirically based candidate biodiversity indicators initially established based on ecological significance to complement the original IndiSeas indicators. The additional selected indicators were: (viii) mean intrinsic vulnerability index of the fish landed catch, (ix) proportion of non-declining exploited species in the surveyed community, (x) catch-based marine trophic index, and (xi) mean trophic level of the surveyed community. Despite the lack of data in some ecosystems, we also selected (xii) mean trophic level of the modelled community, and (xiii) proportion of discards in the fishery as extra indicators. These additional indicators were examined, along with the initial set of IndiSeas ecological indicators, to evaluate whether adding new biodiversity indicators provided useful additional information to refine our under-standing of the status evaluation of 29 exploited marine ecosystems. We used state and trend analyses,and we performed correlation, redundancy and multivariate tests. Existing developments in ecosystem-based fisheries management have largely focused on exploited species. Our study, using mostly fisheries independent survey-based indicators, highlights that biodiversity and conservation-based indicators are complementary to ecological indicators of fishing pressure. Thus, they should be used to provide additional information to evaluate the overall impact of fishing on exploited marine ecosystems

Ecological indicators to capture the effects of fishing on biodiversityand conservation status of marine ecosystems

IndiSeas (“Indicators for the Seas”) is a collaborative international working group that was established in2005 to evaluate the status of exploited marine ecosystems using a suite of indicators in a comparative framework. An initial shortlist of seven ecological indicators was selected to quantify the effects of fishing on the broader ecosystem using several criteria (i.e., ecological meaning, sensitivity to fishing, data avail-ability, management objectives and public awareness). The suite comprised: (i) the inverse coefficient of variation of total biomass of surveyed species, (ii) mean fish length in the surveyed community, (iii)mean maximum life span of surveyed fish species, (iv) proportion of predatory fish in the surveyed community, (v) proportion of under and moderately exploited stocks, (vi) total biomass of surveyed species,and (vii) mean trophic level of the landed catch. In line with the Nagoya Strategic Plan of the Convention on Biological Diversity (2011–2020), we extended this suite to emphasize the broader biodiversity and conservation risks in exploited marine ecosystems. We selected a subset of indicators from a list of empirically based candidate biodiversity indicators initially established based on ecological significance to complement the original IndiSeas indicators. The additional selected indicators were: (viii) mean intrinsic vulnerability index of the fish landed catch, (ix) proportion of non-declining exploited species in the surveyed community, (x) catch-based marine trophic index, and (xi) mean trophic level of the surveyed community. Despite the lack of data in some ecosystems, we also selected (xii) mean trophic level of the modelled community, and (xiii) proportion of discards in the fishery as extra indicators. These additional indicators were examined, along with the initial set of IndiSeas ecological indicators, to evaluate whether adding new biodiversity indicators provided useful additional information to refine our under-standing of the status evaluation of 29 exploited marine ecosystems. We used state and trend analyses,and we performed correlation, redundancy and multivariate tests. Existing developments in ecosystem-based fisheries management have largely focused on exploited species. Our study, using mostly fisheries independent survey-based indicators, highlights that biodiversity and conservation-based indicators are complementary to ecological indicators of fishing pressure. Thus, they should be used to provide additional information to evaluate the overall impact of fishing on exploited marine ecosystems

A risk-based approach to cumulative effect assessments for marine management

Marine ecosystems are increasingly threatened by the cumulative effects of multiple human pressures. Cumulative effect assessments (CEAs) are needed to inform environmental policy and guide ecosystem-based management. Yet, CEAs are inherently complex and seldom linked to real-world management processes. Therefore we propose entrenching CEAs in a risk management process, comprising the steps of risk identification, risk analysis and risk evaluation. We provide guidance to operationalize a risk-based approach to CEAs by describing for each step guiding principles and desired outcomes, scientific challenges and practical solutions. We reviewed the treatment of uncertainty in CEAs and the contribution of different tools and data sources to the implementation of a risk based approach to CEAs. We show that a risk-based approach to CEAs decreases complexity, allows for the transparent treatment of uncertainty and streamlines the uptake of scientific outcomes into the science-policy interface. Hence, its adoption can help bridging the gap between science and decision-making in ecosystem-based management