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Inspired by the growing cries from young climate crisis activists, and noting that net-zero emission legislation is growing in frequency across Europe and globally, this paper briefly discuses some ways in which marine science might respond. Marine science can provide governments support and advice for emission-reducing policies and actions, as well as tackling our own emissions. Supporting government actions will require new and innovative science. While implementing this science, as a community, we can lead by example in bringing about change in the way professionals do business and hence reducing business's overall carbon footprint. After all, if environmental science cannot change, why should the rest of society? [ABSTRACT FROM AUTHOR]

Discard of unwanted catches are common in European fisheries, but reducing or banning this has been given high priority in the proposal for the reform of the Common Fisheries Policy. Although many technical regulations have been introduced to limit unwanted catches, there is little understanding of the underlying socio-economic and institutional incentives causing discard at the fisher level. The paper presents an approach which views discards as a result of decisions made both on deck and at earlier stages of the fishing planning and implementation process. Decisions made by fishers resulting in a more selective fishery are considered “selective behaviour”. It is argued that fishing practices are institutionally embedded within three institutional spheres: “state”, “market”, and “community”, which together with “natural conditions” create incentives and frameworks for discard and selective behaviour. A comprehensive list of factors which may influence discards and selective behaviour is developed and applied to three case studies—all trawl fisheries—in Denmark, Greece, and England. The paper discusses cross-case findings of how the identified factors may create drivers for discard. Finally, a refined list of factors is presented in a tree structure and the usefulness of the list as a tool for analysing drivers for discard and selective behaviour, in a context of developing mitigating measures, is discussed. [ABSTRACT FROM PUBLISHER]

Different marine and coastal activities have diverse economic, environmental, and socio-cultural objectives, which can lead to conflict when these multidimensional activities coincide spatially or temporally. This is sometimes driven by a lack of understanding or other users' needs and consequentially adequate planning and the utilization of a common language is essential. By using a transparent approach based on multi-criteria analysis, we characterize and establish priorities for future development/conservation for all users in the coastal area using six representative European Case Studies with different levels of complexity. Results varied according to location, but significantly it was found that stakeholders tended to favour ecological and social over economic objectives. This paper outlines the methodology employed, the results derived, and the potential for this approach to reduce conflict in coastal and marine waters. [ABSTRACT FROM PUBLISHER]

Simmonds, E. J., Döring, R., Daniel, P., and Angot, V. 2011. The role of fisheries data in the development evaluation and impact assessment in support of European fisheries plans. – ICES Journal of Marine Science, 68: 1689–1698.The European Commission has two formal requirements for developing multi-annual management plan policies: evaluation of the past performance of existing plans and impact assessments (IAs) of the potential benefits of new proposals. The new policies require the evaluation of fishery management in terms of three specific criteria: (i) effectiveness, i.e. the best method to achieve the objectives; (ii) efficiency, the cost-effectiveness, and proportionality; and (iii) consistency, i.e. limiting trade-offs across economic, social, and environmental domains. To develop policy, there is a need to collect relevant information, then to conduct appropriate analyses that provide documentation to support the policy objectives. This paper discusses the data requirements for good environmental, economic, and social understanding of fishery dynamics and management, describing how fishery data are currently linked to the analytical and management evaluation process using examples from 2009 and 2010. The type of information currently used is considered, along with the timetable of data availability, and its effect on historical evaluation and IAs, which are now formally required when any changes to legislation are proposed in the European Union, including following stakeholder consultation. The possibilities and future needs for such data are discussed. [ABSTRACT FROM PUBLISHER]

Johnson, D. 2008. Environmental indicators: their utility in meeting the OSPAR Convention's regulatory needs. – ICES Journal of Marine Science, 65: 1387–1391.The role of marine environmental indicators is clear; selecting indicators to inform management and for the development of accepted frameworks is proving more elusive. The OSPAR Commission, charged with the environmental protection of the Northeast Atlantic, has been applying an ecosystem approach since 1998, applying on a trial basis a system of ecological quality objectives as indicators of ecosystem health for the North Sea. This paper presents a framework for biodiversity monitoring and assessment, and discusses specific issues associated with marine-litter indicators, representing a cell within the matrix of the framework. In the immediate future, European marine legislation will drive the development of environmental indicators in the area, and further harmonization of indicator sets should enhance their utility. [ABSTRACT FROM PUBLISHER]

Enhancement methods have been applied for more than a century throughout the natural range of the Atlantic salmon (Salmo salar L.). Hatcheries, the cornerstone of enhancement programmes, are used to: facilitate colonization of new habitats; restore or rehabilitate stocks to once productive habitats; supplement wild stock production; compensate for major environmental disturbances or problems such as hydroelectric development and acid rain; support fisheries entirely dependent upon hatchery stocking; and foster research and technology development. The benefits from enhancement programmes include: contributing to fisheries and wild stock conservation; increased awareness of the resource and natural environment; technology support for the aquaculture industry; and increased knowledge of salmon biology. The risks from enhancement include: reduced genetic diversity and population fitness; adverse ecological effects; and further degradation and loss of wild stocks. Enhancement is one of a series of management measures that requires careful planning and should be fully integrated within management programmes for the stocks, the resource and its ecosystem. This paper reviews the application of enhancement technology in management programmes for Atlantic salmon in North America and Europe with emphasis on the former. Emphasis is placed on the use of hatcheries because of their prominence as an enhancement tool. [ABSTRACT FROM PUBLISHER]

Within just one human lifetime, the underlying motivation to conserve whales, dolphins and porpoises has shifted from being purely practical and anthropogenic to something much broader, reflecting a desire to protect populations as well as individual animals. In European waters, cetacean conservation currently tends to focus on direct and obvious threats, whereas those originating from widespread human encroachment and consumption patterns tend to be overlooked, even when they are pervasive enough to seriously affect cetacean populations. Cetacean habitat and prey rarely benefit from actual protection (including within Marine Protected Areas), while only moderate and often nominal protection is granted to the cetaceans, without clear conservation baselines and quantitative recovery targets. Meanwhile, historical baselines of cetacean diversity, abundance and distribution appear to be shifting, and the memory of past culling campaigns is fading. Here, we argue that cetacean conservation should go beyond just avoiding further population decline or warding off the extinction of single species. Allowing only the most opportunistic and resilient species to persist, often by merely attempting to mitigate direct mortality (e.g. bycatch in fishing gear), should not pass for actual cetacean conservation. We should strive instead for the full recovery of multiple species throughout their historical ranges. [ABSTRACT FROM AUTHOR]

The importance of social and economic factors, in addition to biological factors, in fisheries management is being increasingly recognised. However, exploration of trade-offs between biological, social, and economic factors under different sustainable catch limits for recreational and commercial fisheries is limited, especially in Europe. The European sea bass (Dicentrarchus labrax) is valuable and important for both commercial and recreational fisheries. Stocks have rapidly declined and management measures have been implemented, but trade-offs between social, biological, and economic factors have not been explicitly considered. In this study, a system dynamics model framework capturing biological and economic elements of the European sea bass fishery was developed and refined to incorporate a catch limit reflecting sustainable fishing with adjustable partition between recreational and commercial sectors, under low, medium, or high recruitment. Model outputs were used to explore the relative impact of different catch allocations on trade-offs between biological sustainability and economic impact when recruitment was limiting or not. Recruitment had a large impact on the fish population dynamics and the viability of the sectors. At high and moderate recruitment, management contributed to stock sustainability and sector economic impact, but recruitment is important in determining the balance between sectors. [ABSTRACT FROM AUTHOR]

The development of the marine renewable energy and offshore aquaculture sectors is susceptible to being affected by climate change. Consequently, for the long-term planning of these activities, a holistic view on the effects of climate change on energy resources and environmental conditions is required. Based on present climate and future climate scenario, favourable conditions for wind and wave energy exploitation and for farming six marine fish species are assessed using a suitability index over all European regional seas. Regarding available energy potential, the estimated changes in climate do not have direct impacts on the geographic distribution of potential regions for the energy industry (both wind and wave based), that is they pose no threat to this industry. Long-term changes in environmental conditions could however require adaptation of the aquaculture sector and especially of its exploitation areas. Opportunities for aquaculture expansion of the assessed species are identified. Possibilities for co-location of these activities are observed in the different climate scenarios. The evaluation of potential zones for the exploitation of marine renewable energy resources and offshore aquaculture represents a stepping-stone, useful for improving decision-making and assisting in the management of marine economies both in the short-term and in the long-term development of these sectors. [ABSTRACT FROM AUTHOR]

We describe an investigation into the challenges faced by fishing gear technologists inspiring the voluntary uptake of proven fishing gear by fishers, defined as fishing gear that has satisfied research objectives following field trials between fishers and fishing gear technologists. We applied a multifaceted approach to understand how the uptake rate of this fishing gear can be achieved based on the results of a 3-year ICES-FAO Working Group on Fishing Technology and Fish Behaviour (WGFTFB) topic group on change management in fisheries. This was supported by an online survey and interview of WGFTFB members, comprising mainly of fishing gear technologists and researchers from Europe and North America, and a review of projects in the US Northwest Atlantic to evaluate the performance of fishing gear in close collaboration with fishers. We found that widespread voluntary uptake of proven fishing gear by fishers is rare, and usually takes place over many years if at all. The uptake of this gear was more likely occur in the face of perceived financial benefit or impending regulation, although financial benefit was not always sufficient inducement for fishers change their gear. The effectiveness of outreach programmes to inspire the uptake of this gear was also found to be questionable, and the efficacy of incentives was limited and inconsistent, even if the informational deficit of fishers was low. Few WGFTFB members were found to use change management models such as that by Kotter, and they relied mainly on informal, ad hoc approaches to inspire the uptake of proven fishing gear. Based on our findings we posit a need to (i) examine our assumptions about the behaviour of fishers, (ii) augment communication of the results of fishing gear research, (iii) focus on emotions to overcome motivational deficits, and (iv) consider how the application of change management models can improve the ability of fishing gear technologists to inspire the uptake of proven fishing gear by fishers. [ABSTRACT FROM AUTHOR]

The rivers in northernmost Europe support many of the largest wild Atlantic salmon stocks supplying up to 60% of the total annual catch in the world, but very little is known about their relative contributions to coastal fisheries. We generated a comprehensive Atlantic salmon genetic baseline consisting of 185 populations along the Norwegian, Barents and White Sea coasts, genotyped for a high number of genetic markers, which has a dense geographical coverage and includes all notable stocks in the region. The hierarchical genetic structure observed was the basis for defining 7 regional and 26 local re3porting groups (RGs) enabling practical implementation of genetic stock identification (GSI). The GSI accuracy varied across populations and the study area, depending on the level of genetic structuring, but a high level of accuracy was achieved when individuals were classified to regional (97%) or to local (90%) RGs. Simulations showed that salmon from the majority of the largest populations in northernmost Europe can be reliably identified in Norwegian and Russian coastal mixed-stock fisheries. The baseline will be an invaluable resource for development of future adaptive management regimes for Atlantic salmon in northern Europe. [ABSTRACT FROM AUTHOR]

The world's fish stocks, although renewable, are a finite resource. European capture fisheries have remained stagnant in terms of volume for many years. To remain profitable, fishers are looking for new opportunities to diversify, reduce costs, and maximize profits. The targeted fishing of boarfish (Capros aper) in Europe is an excellent example of such adaptation. Using this fishery as a case study, we highlight how established fisheries are adapting to changes faced by the industry. We begin by compiling the knowledge to date on the taxonomy, biology, and ecology of the understudied boarfish and go on to provide a comprehensive overview of its expansion as a targeted fishery in Europe, examining the range of valorization options currently being investigated. [ABSTRACT FROM AUTHOR]

The brown shrimp (Crangon crangon) fishery is economically one of the most important fisheries in the North Sea. Fishing is unregulated, apart from the number of licenses and technical measures. The fishery has long been considered sustainable in terms of the effect on the target species, even though annual stocks are not regularly assessed. Average landings constantly increased annually and since 2000 have been 40% higher than in the 1980s and 1990s. Because brown shrimp lack a clear age structure and reproduce almost year-round, an agebased stock assessment is not possible. In the absence of a formal estimate of stock size, it is difficult to judge whether current fishing practices can still be considered sustainable. Here, we use annual survey data collected during peak occurrence in late summer to obtain a depth- and area-stratified, swept-area estimate for the period 1970-2015. The resulting estimate of the total commercial-size shrimp biomass varied between 4000 and 21 000 tonnes over the years. Both parametric and non-parametric methods arrived at very similar results. In combination with length-based mortality estimates (as a proxy for production/biomass ratio), knowledge on the seasonal occurrence, catchability, gear efficiency, and their variation, total adult annual biomass production was estimated. Values ranged between 38 000 and 216 000 tonnes and overlapped at the lower end with total annual commercial landings, which varied between 8000 and 38 500 tonnes, indicating that in some years (1977, 1998, 2007), the larger part of the total brown shrimp production was harvested. Annual brown shrimp landings have gradually increased since the series started, whereas no trend in standing biomass and production was detected. Concurrent with the increase in landings, natural mortality of shrimp by predation has diminished. Considering the increase in fishing pressure and unknown consequence if natural predators recover or shrimp recruitment decreases, the lack of management for the brown shrimp fishery needs to be reconsidered. [ABSTRACT FROM AUTHOR]

To reduce the practice of discarding commercially fished organisms, several measures such as a discard ban and extra allowances on top of landings quotas (“catch quota”) have been proposed by the European Commission. However, for their development and successful implementation, an understanding of discard patterns on a European scale is needed. In this study, we present an inter-national synthesis of discard data collected on board commercial, towed-gear equipped vessels operating under six different national flags spanning from the Baltic to the Mediterranean Seas mainly between 2003 and 2008. We considered discarded species of commercial value such as Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), European hake (Merluccius merluccius), and European plaice (Pleuronectes platessa). Comparisons of discard per unit effort rates expressed as numbers per hour of fishing revealed that in the Mediterranean Sea minimum size-regulated species such as hake are generally discarded in much lower numbers than elsewhere. For most species examined, variability in discard rates across regions was greater than across fisheries, suggesting that a region-by-region approach to discard reduction would be more relevant. The high uncertainty in discard rate estimates suggests that current sampling regimes should be either expanded or complemented by other data sources, if they are to be used for setting catch quotas. [ABSTRACT FROM PUBLISHER]

erter, K., Weltersbach, M. S., Strehlow, H. V., Vølstad, J. H., Alós, J., Arlinghaus, R., Armstrong, M., Dorow, M., de Graaf, M., van der Hammen, T., Hyder, K., Levrel, H., Paulrud, A., Radtke, K., Rocklin, D., Sparrevohn, C. R., and Veiga, P. 2013. Unexpectedly high catch-and-release rates in European marine recreational fisheries: implications for science and management. – ICES Journal of Marine Science, 70: .While catch-and-release (C&R) is a well-known practice in several European freshwater recreational fisheries, studies on the magnitude and impact of this practice in European marine recreational fisheries are limited. To provide an overview of the practice and magnitude of C&R among marine recreational anglers in Europe, the existing knowledge of C&R and its potential associated release mortality was collected and summarized. The present study revealed that in several European countries over half of the total recreational catch is released by marine anglers. High release proportions of >60% were found for Atlantic cod (Gadus morhua), European sea bass (Dicentrarchus labrax), pollack (Pollachius pollachius), and sea trout (Salmo trutta) in at least one of the studied European countries. In the case of the German recreational Baltic Sea cod fishery, release proportions varied considerably between years, presumably tracking a strong year class of undersized fish. Reasons for release varied between countries and species, and included legal restrictions (e.g. minimum landing sizes and daily bag limits) and voluntary C&R. Considering the magnitude of C&R practice among European marine recreational anglers, post-release mortalities of released fish may need to be accounted for in estimated fishing mortalities. However, as the survival rates of European marine species are mostly unknown, there is a need to conduct post-release survival studies and to identify factors affecting post-release survival. Such studies could also assist in developing species-specific, best-practice guidelines to minimize the impacts of C&R on released marine fish in Europe. [ABSTRACT FROM PUBLISHER]

Deporte, N., Ulrich, C., Mahévas, S., Demanèche, S., and Bastardie, F. 2012. Regional métier definition: a comparative investigation of statistical methods using a workflow applied to international otter trawl fisheries in the North Sea. – ICES Journal of Marine Science, 69: 331–342.The European Common Fisheries Policy recognizes the importance of accounting for heterogeneity in fishing practices, and métier-based sampling is now at the core of the EU Data Collection Framework. The implementation of such an approach would require Member States to agree on the standard regional métier definitions and on practical rules to categorize logbook records into métiers. Several alternative approaches have been used in the past to categorize landings profiles, but no consensus has yet emerged. A generic open-source workflow is developed to test and compare a selection of methods, including principal components analysis (PCA), hierarchical agglomerative clustering (HAC), K-means, and Clustering LARge Applications (CLARA), and to provide simple allocation rules. This workflow is applied to a unique regional dataset consisting of bottom-trawl logbooks of five North Sea countries. No method proved to be infallible, but combining PCA with either CLARA or HAC performed best. For 2008, a hierarchical classification with 14 species assemblages is proposed. Discriminant analysis proved more robust than simple ordination methods for allocating a new logbook record into an existing métier. The whole approach is directly operational and could contribute to defining more objective and consistent métiers across European fisheries. [ABSTRACT FROM PUBLISHER]

Lorance, P., Agnarsson, S., Damalas, D., des Clers, S., Figueiredo, I., Gil, J., and Trenkel, V. M. 2011. Using qualitative and quantitative stakeholder knowledge: examples from European deep-water fisheries. – ICES Journal of Marine Science, 68: 1815–1824.Stakeholder knowledge was collected through questionnaires and cognitive maps and used to summarize biological, environmental, technical, management, and socio-economic factors for several deep-water fisheries, identifying regional management issues and solutions. The questionnaires and cognitive maps revealed different technical, environmental, and management concerns in these fisheries. Dissatisfaction with management was more at an implementation than a conceptual level, because the existing management measures were mostly considered fit for purpose. Further, catch-and-effort data provided by the fishing industry were used to calculate standardized landings per unit effort. The results suggested different trends over time for three deep-water stocks exploited by the same fleet. The examples demonstrate how stakeholder involvement and use of qualitative knowledge and quantitative data might improve the management process and stock assessments when data are limited. [ABSTRACT FROM PUBLISHER]

Hinrichsen, H-H., Dickey-Collas, M., Huret, M., Peck, M. A., and Vikebø, F. B. 2011. Evaluating the suitability of coupled biophysical models for fishery management. – ICES Journal of Marine Science, 68: 1478–1487.The potential role of coupled biophysical models in enhancing the conservation, management, and recovery of fish stocks is assessed, with emphasis on anchovy, cod, herring, and sprat in European waters. The assessment indicates that coupled biophysical models are currently capable of simulating transport patterns, along with temperature and prey fields within marine ecosystems; they therefore provide insight into the variability of early-life-stage dynamics and connectivity within stocks. Moreover, the influence of environmental variability on potential recruitment success may be discerned from model hindcasts. Based on case studies, biophysical modelling results are shown to be capable of shedding light on whether stock management frameworks need re-evaluation. Hence, key modelling products were identified that will contribute to the development of viable stock recovery plans and management strategies. The study also suggests that approaches combining observation, process knowledge, and numerical modelling could be a promising way forward in understanding and simulating the dynamics of marine fish populations. [ABSTRACT FROM PUBLISHER]

Hammer, C., von Dorrien, C., Hopkins, C. C. E., Köster, F. W., Nilssen, E. M., St John, M., and Wilson, D. C. 2010. Framework of stock-recovery strategies: analyses of factors affecting success and failure. – ICES Journal of Marine Science, 67: 1849–1855. The EU FP6 UNCOVER project was aimed at producing a rational scientific basis for developing recovery strategies for some ecologically and socio-economically important fish stocks/fisheries in European seas. The immediate objectives were to identify changes experienced during stock depletion/collapses, to understand prospects for recovery, to enhance the scientific understanding of the mechanisms of recovery, and to formulate recommendations on how best to implement long-term management/recovery plans. We extended an earlier analysis conducted within the project of 13 performance criteria in relation to the recovery of more than 30 fish stocks/fisheries worldwide by multivariate exploratory analysis (canonical correspondence analysis), followed by model building [discriminant analysis (DA)] to quantify the relative importance of key performance criteria, singly or combined. Using the existing database, DA indicated that the four best additive predictors of successful recovery were “rapid reduction in fishing mortality”, “environmental conditions during the recovery period”, “life-history characteristics” of the target stock, and “management performance criteria”. The model classified the status “recovered” and “non-recovered” assigned originally with nearly 100% accuracy. [ABSTRACT FROM PUBLISHER]

van Hoof, L. 2010. Co-management: an alternative to enforcement? – ICES Journal of Marine Science, 67: 395–401.The decline in fish stocks worldwide has often been attributed to problems inherent with resources being treated as common property. Government is usually called upon to define and implement solutions, but the issues society face today cannot be dealt with by the classical, state-centred system of the industrial society. In this article, the Dutch case of fisheries management is used to demonstrate how a government-orientated solution, such as the recently inaugurated EU Community Fisheries Control Agency, and a governance-type solution, such as co-management, relate to each other and whether a partnership between government and the market, such as co-management, can serve as an alternative to direct government enforcement. Although the Dutch case is not a true-bred form of co-management, but rather a case of co-enforcement, it can be used to service a theoretical assessment of the possibilities of co-enforcement at a European scale. [ABSTRACT FROM PUBLISHER]

Ganzedo, U., Zorita, E., Solari, A. P., Chust, G., Santana del Pino, A., Polanco, J., and Castro, J. J. 2009. What drove tuna catches between 1525 and 1756 in southern Europe? – ICES Journal of Marine Science, 66: 1595–1604.From 1525 to 1756, catches of tuna in almadrabas (trapnets) fluctuated greatly, but the overall trend was a downwards one. The aim of this study is to assess the potential influence of climatic factors on tuna fishing. We performed time-series analysis of the climate over the years 1525–1756 and determined whether such events can be related to historical data on bluefin tuna catches in the almadrabas of Medina Sidonia. We used a generalized linear model to relate the tuna catches to climatic parameters. We carried out variance partitioning analysis of tuna catches to assess the relative contribution of climate from temporal autocorrelation. The temporal autocorrelation in tuna catches was used as a surrogate for the contribution of the population dynamics to variation in the catch series. The results indicated that climate accounted for up to 12.3% of the total variance, the temporal effects (autocorrelation) accounted for up to 38.8% of the total variance, and up to 35.7% of the catch was accounted for by the joint effect of the two components. The significant variance accounted for by climate suggests that low temperatures during the Maunder minimum (the so-called “The Little Ice Age”, years 1640–1715) may have reduced both recruitment and abundance of tuna in the North Atlantic and the Mediterranean. Our findings suggest that both environmental and population dynamic components played an important role in regulating the almadraba catches in Medina Sidonia. [ABSTRACT FROM PUBLISHER]

Stocks of European eel (Anguilla anguilla) have declined continuously and steadily, since 1980. A model, GEMAC, namely Glass Eel Model to Assess Compliance, has been developed with the objective of assessing anthropogenic impacts on glass eels in estuaries and evaluating the effects of management measures, to support initiatives aimed at helping the eel stocks recover. The model is described and applied to two estuaries with contrasting anthropogenic pressures: the Vilaine and the Garonne. It assesses the proportion of settled glass eels relative to a non-impacted situation with current (%S/R) or pristine recruitment (%S/R0). The estimated %S/R (%S/R0) is 5.5% (1.1%) for the Vilaine and 78% (19%) for the Garonne, in accord with the different levels of anthropogenic pressure in these two estuaries. A sensitivity analysis shows that the assessment of %S/R is accurate, and that in a data-poor context, the %S/R is under-assessed, as required by the precautionary approach. Seven management scenarios are explored all aiming to halve the anthropogenic pressure, but in fact leading to different levels of glass eel escapement, from almost zero to a 13-fold increase. This variation emphasizes the need for the estuarine context of eel stock management to be carefully evaluated for effectiveness when implementing management measures. [ABSTRACT FROM PUBLISHER]

Aprahamian, M. W., Walker, A. M., Williams, B., Bark, A., and Knights, B. 2007. On the application of models of European eel (Anguilla anguilla) production and escapement to the development of Eel Management Plans: the River Severn. – ICES Journal of Marine Science, 64: 1472–1482.The European eel stock has declined significantly since the 1980s, and the Eel Recovery Plan of the European Commission requires Member States to develop river basin Eel Management Plans (EMPs) that will achieve an escapement of silver eels that equals or exceeds 40% of the escapement biomass that would be produced in the absence of human activities. However, because silver eel escapement is not quantified within the UK, a modelling approach is required to estimate potential and actual escapement, and to assess the likely effects of management measures. We focus on two approaches developed in the UK, the Reference Condition Model (RCM) and the Scenario-based Model for Eel Populations (SMEP), and illustrate how such approaches can be used in EMPs using selected data from the River Severn. The RCM results indicate that the yellow eel population in the River Severn basin may be just 30–40% of the potential density indicated by reference conditions derived from a selection of rivers between the late 1970s and the early 1980s. The challenges of applying a model designed to be as realistic of eel production as possible, and the limited data on natural eel habitat and eel production in the Severn, preclude a SMEP analysis similar to that of the RCM, but simulations based on a simplified basin description and eel survey data from the early 1980s illustrate the potential of this model to assess compliance and test management scenarios. [ABSTRACT FROM PUBLISHER]

Degnbol, P., and McCay, B. J. 2006. Unintended and perverse consequences of ignoring linkages in fisheries systems. – ICES Journal of Marine Science, 64: 793–797.The development of fisheries management strategies within institutions such as national governments, the EU, and ICES includes explicit or implicit decisions on longer term management objectives and performance criteria, on the relevant knowledge base for tactical management decisions, on decision rules regarding fisheries in the current or forthcoming fishing season, and on the implementation framework. These decisions, moreover, must be relevant to the characteristics of the fisheries and the stocks being exploited. The development of management strategies must be based, therefore, on an understanding of the overall fisheries system and linkages among its components. Based on recent examples in Europe and North America, we discuss how a failure to understand the linkages in the fisheries system may lead to management strategies that fail to achieve their objectives, and how an understanding of these linkages can inform the development of strategies that are more likely to achieve policy objectives. [ABSTRACT FROM PUBLISHER]

Patterson, K., and Résimont, M. 2007. Catch and stability in landings: the response of fisheries to scientific advice and TACs. – ICES Journal of Marine Science, 64: 714–717. Stability in total allowable catch (TAC) and landings is a principal demand from the fishing sector, and sufficient experience has now been gained in applying the Common Fisheries Policy in European Atlantic waters to allow an initial review of the stability in landings across stocks. Available information is compared across a large number of stocks to determine the relative influence of scientific advice on relative changes in landings, on the decision-making process, and on resulting rates of fishing mortality. The approach differs from the conventional model approaches based on population dynamics, but allows conclusions to be drawn based on recent experience in management. The conclusion is that the most important factor enhancing long-term stability is a low rate of fishing mortality, but that following scientific advice on a year-to-year basis would decrease stability. Unless TACs varied considerably, they did not appear to affect variations in landings significantly. [ABSTRACT FROM PUBLISHER]

Suuronen, P., and Sardà, F. 2007. The role of technical measures in European fisheries management and how to make them work better. – ICES Journal of Marine Science, 64: 751–756. Technical measures such as gear restrictions are commonly used in European fisheries management. Many of the measures are aimed primarily at protecting juveniles. Although they are assumed to provide both biological and economic benefits, proper evaluation of their effects relative to what is intended is often not possible because of a lack of adequate follow-up studies. Moreover, technical measures usually are used in conjunction with other management measures, which greatly complicate the analysis. We describe the principal factors affecting their effectiveness to find the approaches that may help to improve performance. Many regulations are enforced inconsistently, and their implementation is often less restrictive than originally intended. Moreover, trying to solve one problem frequently creates new ones. The successful use of technical measures appears to depend largely on their acceptance by industry. Measures that increase costs or reduce earnings are unattractive, so if short-term effects are not accounted for, the potential long-term gains may never materialize. Successful management actions have addressed these problems. Although technical measures may conserve resource, particularly to supplement a broader management policy, new regulations should be planned with great care, and any measures should be tested properly before implementation. [ABSTRACT FROM PUBLISHER]

Symes, D. 2007. Fisheries management and institutional reform: a European perspective. – ICES Journal of Marine Science, 64: 779–785. [ABSTRACT FROM PUBLISHER]

Pawson, M. G., Pickett, G. D., Leballeur, J. Brown, M., and Fritsch, M. 2007. Migrations, fishery interactions, and management units of sea bass (Dicentrarchus labrax) in Northwest Europe. – ICES Journal of Marine Science, 64: 332–345. A total of 4959 sea bass was tagged between 2000 and 2005 around the coasts of England, Wales, southern Ireland, and the Channel Isles to investigate whether movement patterns documented in 1987 have changed and to estimate the level of competition for sea bass between inshore and offshore fisheries. Most (54%) of the recaptures of adult bass (fish >40 cm) tagged inshore and made between May and October were within 16 km of the release positions. From November on, an increasing proportion was recaptured at least 80 km south or southwest of tagging sites. Bass tagged on offshore spawning grounds in March and April showed reciprocal movement, 75% of recaptures between May and October being at least 80 km from the release site. These observations reaffirm the hypothesis that adult sea bass may move considerable distances to offshore winter spawning areas, but there was little evidence of the spawning migrations between the North Sea and the western Channel that were observed in the early 1980s. Just 3% of the recaptures of bass >36 cm tagged in UK inshore fisheries were reported from the offshore pairtrawl fishery, whereas half the recaptures of bass tagged in that fishery were made inshore along the UK coast. When weighted by the respective catches, this suggests that the effects of management measures implemented in the UK inshore fishery are largely restricted to that fishery. A proposal for stock units for assessment and management of NW European sea bass fisheries is presented. [ABSTRACT FROM PUBLISHER]

Small pelagic fish are known to aggregate into schools and clusters of schools. It is commonly assumed that the number of such schools and clusters, as well as their size and densities, will vary with the stock abundance. We have carried out a PCA based meta-analysis, using series of acoustic survey data from five different locations in Europe to examine this assumption. The study concluded that there was no discernible relationship between stock abundance and the number of schools seen, or on the clustering of those schools. The study also showed that the number and structure of the school clusters was strongly correlated with the number of schools seen. An increased number of schools in an area tended to be linked with denser clusters (more schools per kilometre) and a higher occupation of the survey area by those clusters. There was also a weaker tendency to find more clusters. It is not clear whether these relationships and the absence of a link to abundance are due to density independence in aggregation patterns or whether such density dependence is only functional at relatively low stock abundance levels. [ABSTRACT FROM PUBLISHER]

No assessment of the state of the European eel stock is available due to the absence of adequate data for many areas of the continent. In contrast to past efforts which turned to complete the traditional catch composition data, and which met with little success, we will try to develop a simplified cohort-model (based on life stage, rather than age or size), simple enough for the available data. [ABSTRACT FROM PUBLISHER]

In this comparative study of fishery production from 14 semi-enclosed marine statistical areas around Europe, GIS techniques were used to estimate some simple geographical parameters in both these areas and their surrounding catchments. Indices included the ratio of catchment area to sea area, chlorophyll-a (Chl-a) pigmentation intensity from remote sensing imagery and a simple index of the degree of geographical enclosure. These indices were compared with the ratio of pelagic to demersal plus invertebrate landings (the P/D ratio). The P/D ratio appears to be a proxy for the differential impact of nutrients on pelagic and benthic system, in that benthic/demersal components are negatively affected by hypoxia resulting from excess primary production, which has less negative effects, (or may even be positive), for pelagic fish production. P/D ratios shows a wide dynamic range from <1.0 for nutrient-limited or oligotrophic seas (e.g. the Aegean and Ionian) to 10 and more for more eutrophic water bodies such as the Black and Azov Seas. Chl-a appears related to the degree of enclosure, perhaps implying significant nutrient run-off from land, while the P/D ratio appears to be correlated with the mean Chl-a value. [ABSTRACT FROM PUBLISHER]