Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    New tuna regimes
    Yeeting, Agnes David - \ 2017
    Wageningen University. Promotor(en): S.R. Bush, co-promotor(en): H.P. Weikard; V. Ram-Bidesi; M. Bailey. - Wageningen : Wageningen University - ISBN 9789463438308 - 154
    fisheries - marine fisheries - tuna - sustainability - environmental policy - governance - economic policy - pacific ocean - environmental economics - visserij - zeevisserij - tonijn - duurzaamheid (sustainability) - milieubeleid - governance - economisch beleid - grote oceaan - milieueconomie
    governing sustainability and equity in the Western and Central Pacific Ocean
    Towards sustainable tuna fishing: understanding the role of private incentive mechanisms
    Tolentino-Zondervan, Frazen - \ 2017
    Wageningen University. Promotor(en): A.G.J.M. Oude Lansink; S.R. Bush, co-promotor(en): P.B.M. Berentsen. - Wageningen : Wageningen University - ISBN 9789463436236 - 205
    tuna - fishing - sustainability - sea fishing - marine fisheries - marine animals - environmental protection - value chain analysis - decision making - philippines - south east asia - business economics - tonijn - vis vangen - duurzaamheid (sustainability) - sportzeevisserij - zeevisserij - zeedieren - milieubescherming - waardeketenanalyse - besluitvorming - filippijnen - zuidoost-azië - bedrijfseconomie

    Unsustainable fishing practices, including the use of non-selective fishing methods and Illegal Unreported and Unregulated (IUU) fishing, contribute to the decline of tuna fish stocks in the Western and Central Pacific Ocean (WCPO). This has led to emergence of different public and private governance arrangements to foster the sustainable exploitation of tuna stocks. This thesis focuses on the performance of three innovative private incentive mechanisms: Fishery Improvement Projects (FIPs), International Seafood Sustainability Foundation’s Pro-active Vessel Register and eco-FADs, and Marine Stewardship Council (MSC) certification, to deliver economic incentives for improved production. The overall objective of this thesis is to evaluate the extent to which private incentive mechanisms influence Filipino fishers’ decision to improve their fishing practices.

    In order to address the overall objective, this thesis first analyses and compares the ways existing private incentive mechanisms influence the upgrading strategies of Filipino tuna fishers in the value chains (in chapter 2). Second, it evaluates the important determinants for small-scale handline fishers’ decisions to participate in two FIPs for yellowfin tuna in the Philippines (in chapter 3). Third, it examines the effect of MSC certification on the allocation of fishing days by Filipino purse seiners operating in Parties to Nauru Agreement (in chapter 4). And finally, it analyses the profitability of investments in measures needed to comply with private incentive mechanisms by Filipino purse seiners (in chapter 5).

    The findings show that overall, the incentive mechanisms are able to improve the practices of fishers, however only to a limited extent. The first two chapters (chapters 2 and 3) show that producers first need to have the capabilities to meet the requirements of private incentive mechanisms, so that they can be included in the value chain and that they can realise the incentives offered by these mechanisms. However, being capable does not guarantee that producers will improve their practices. As shown in the last two chapters (chapters 4 and 5), producers must also have the willingness to upgrade, based on their risk attitude and on the ability of the economic incentive to cover the additional costs and to compensate for the increase of the risks of participation of producers. Given that producers have the availability of capabilities to upgrade and that the benefit is sufficient to opt for participation, then producers may decide to improve their practices, which may contribute to the sustainability improvement goal of private incentive mechanisms. As a consequence of this finding, the incentives, inclusiveness, and improvements must be taken into account in both the design and implementation of private incentive mechanisms.

    Monitoring cod catches of the Dutch demersal fleet in 2016
    Hal, R. van; Machiels, M.A.M. - \ 2017
    IJmuiden : Wageningen Marine Research (Wageningen Marine Research Report C056/17) - 29
    monitoring - cod - beam trawling - pulse trawling - demersal fisheries - marine fisheries - fish catches - north sea - gadus morhua - monitoring - kabeljauw - boomkorvisserij - pulsvisserij - demersale visserij - zeevisserij - visvangsten - noordzee - gadus morhua
    This report presents the results of the cod monitoring program 2016. The research was commissioned by the Dutch Ministry of Economic Affairs within the EZ-program Beleidsondersteunend Onderzoek. Cod catches of the vessels in the fleet segments BT2 (beam trawl and pulse trawl) and TR (otter trawls and seines) need to be monitored yearly, due to the Dutch implementation of the European cod recovery plan. The European cod recovery plan restricts the fishing effort of European fleets catching cod. Fishing effort, based on historical track records, is allocated to different gear groups. Fishing effort can be transferred between gear groups by use of conversion factors. In the Netherlands fishing effort is transferred yearly from the BT2 gear group to the TR group, based on a national conversion factor of 1:3 (BT:TR) kWdays instead of the European conversion factor of 1:16. This is because the cod catches in the Dutch TR fleet are not as high as the European conversion factor implies. In order to substantiate for the national conversion factor, the Dutch government is obliged to report cod catches per unit of effort (CpUE) of the vessels in these gear groups to the European Commission. An overview is provided of the fishing activity, the cod landings and the cod landings per unit of effort of the various gear categories in the BT2 and the TR fleet segments during the year 2016. First the cod Catch per Unit of Effort (CpUE) transition ratio between the BT2 on the one hand and the TR1C plus TR2 fleet segments on the other hand was calculated. And secondly the percentage of cod avoidance trips – trips during which 5% or less cod was caught – in the TR-fleet were calculated. The TR fleet has a higher cod CpUE on average than the BT fleet. When the cod targeted fisheries (TR1AB) are not taken into account, the CpUE effort transition ratio (TR1C+TR2): BT2 of 2016 lies between 4.2:1 and 5.7:1, depending on whether the ratio is calculated on the basis of minimum or maximum cod discards estimation by the Scientific, Technical and Economic Committee for Fisheries (STECF) respectively whereby in the minimum calculation the vessels participating in the CCTV program are excluded. Based on average discards estimations including all vessels, the ratio is 5.1:1. The percentage of cod avoidance trips, fishing trips with 5% cod or less in the total catches, in the TR1C and the TR2 fleets were 94% and 96% in 2016 respectively. These percentages are based on average STECF cod discards estimations. When minimum or maximum discards estimations are used, the calculated percentages of cod avoidance trips does not vary more than 2 or 3% from the percentage based on average estimations.
    The KB WOT Fisheries Programme carried out in 2015
    Damme, C.J.G. van; Verver, S.W. - \ 2017
    IJmuiden : Stichting Wageningen Research, Centre for Fisheries Research (CVO) (CVO report / Centre for Fisheries Research 16.007) - 57
    visserijbeheer - zeevisserij - visserijbeleid - visbestand - schaal- en schelpdierenvisserij - discards - onderwaterakoestiek - visstand - vismethoden - fishery management - marine fisheries - fishery policy - fishery resources - shellfish fisheries - discards - underwater acoustics - fish stocks - fishing methods
    The KB WOT Fisheries programme is established to maintain and develop the expertise needed to carry out the statutory obligations of the Netherlands in fisheries monitoring and advice. It is also a flexible program which responds to changes over time in WOT requirements, fisheries management and policy needs. While maintaining the core expertise and flexibility, the KB WOT programme also strives to be innovative and participate in the development of fisheries science. The programme operates within the context of the Common Fisheries Policy (CFP), the EU Marine Strategy Framework Directive (MSFD) and the EU Maritime Policy. The KB WOT fisheries programme is established annually and positioned around a number of themes. In 2015 14 projects were originally awarded. However, one project could not meet all the original objectives and with the remaining budget a 15th project was started on the tool development for fish ageing and maturity staging. These 15 projects were successfully completed. The programme focused on the research into the impact of fisheries on the seafloor, development of tools for electronic monitoring, data storage and dissemination and method development for assessment of marine resources. As always the core element of the KB WOT Fisheries was maintaining and developing key expertise for the WOT programme. A large part of the budget was therefore used for projects that standardise fish ageing, provide quality control of discard, ichthyoplankton and shellfish monitoring and development of fisheries acoustics techniques and expertise. These topics are vital for the quality of fish stock assessments and management. Of the 15 projects funded in 2015, seven were carried out in collaboration with institutes outside the Netherlands. As resources and expertise from these other countries contribute to the KB WOT Fisheries programme, these collaborations provided a large amount of added value to the programme. Another large part of the KB WOT resources is specifically dedicated to international collaboration and exchange of science. This ensures that Wageningen Marine Research researchers remain at the centre of scientific developments and international fisheries research. The programme was also very productive in terms of publications, presentations and developing new methods or tools for fisheries research. Over 15 international presentations were given at meetings, workshops and symposia, and 22 international and national reports written. 8 new methods or models were developed, 3 peer reviewed publications published and 5 scientific publications prepared.
    KB WOT Fisheries 2017 : maintaining excellence and innovation in fisheries research
    Damme, C.J.G. van; Verver, S.W. - \ 2017
    IJmuiden : Stichting Wageningen Research, Centre for Fisheries Research (CVO) (CVO report / Centre for Fisheries Research 17.006) - 89
    remote sensing - schaal- en schelpdierenvisserij - visserijbeheer - landmeetapparatuur - discards - visvangsten - zeevisserij - remote sensing - shellfish fisheries - fishery management - surveying instruments - discards - fish catches - marine fisheries
    The KB WOT Fisheries programme is developed to maintain and advance the expertise needed to carry out the statutory obligations in fisheries monitoring and advice of The Netherlands. The contents of the KB WOT Fisheries programme for 2017 reflects the scientific and management needs of the WOT fisheries programme. The strength of KB WOT Fisheries lies in the top-down development of the programme while allowing bottom-up input, with calls for proposals, to secure innovation. To avoid missing research priorities relevant to WOT and EZ needs, the programme is built from a closed call for proposals to WOT Fisheries project leaders. To keep the innovation WOT project leaders are requested to seek input from other Wageningen Marine Research scientists. The KB WOT Fisheries programme will fund 13 projects in 2017 which will focus on remote sensing of fish and shell fish in the ecosystem, new methods and tools for surveys, discard and catch sampling and investigating the effects of fisheries. International exchange of new expertise and developments, as well as continuous quality assurance, forms a major part of the programme.
    The KB WOT Fisheries Programme carried out in 2016
    Damme, C.J.G. van; Verver, S.W. - \ 2017
    IJmuiden : Stichting Wageningen Research, Centre for Fisheries Research (CVO) (CVO report / Centre for Fisheries Research 17.007) - 63
    visserijbeheer - visbestand - visserijbeleid - zeevisserij - schaal- en schelpdierenvisserij - monitoring - onderwaterakoestiek - vis - fishery management - fishery resources - fishery policy - marine fisheries - shellfish fisheries - monitoring - underwater acoustics - fish
    Maintaining and developing the expertises needed to execute the Dutch fisheries monitoring and advice statutory obligations is the core of the KB WOT Fisheries programme. As fisheries management and policy needs, and thus the WOT requirements, change over time, the KB WOT programme needs to be flexible to respond to these changes. The KB WOT programme seeks to be inventive and participate in the fisheries science development, while maintaining the core expertises and flexibility. The programme operates within the context of the Common Fisheries Policy (CFP), the EU Marine Strategy Framework Directive (MSFD) and the EU Maritime Policy. The KB WOT fisheries programme is established annually and positioned around a number of themes. In 2016 17 projects were originally awarded. However, one project could not meet all the original objectives and with the remaining budget a new project was started on the tool development for monitoring catches on board commercial vessels. The 18 projects within the programme were successfully completed. The focus of the programme in 2016 was on research into mapping the seafloor, development of tools and framework for monitoring catches on board commercial vessels, data storage and accessibility and method development for assessment of marine resources. As the basis of the KB WOT Fisheries is maintaining and developing key expertise for the WOT programme, a considerable part of the funds was used for projects that standardise fish ageing, fish and shellfish monitoring and development of fisheries acoustics techniques and expertise. These subjects are essential for ensuring the high quality of fish stock assessments and management. Of the 18 projects funded in 2016, six were carried out in international collaboration with other institutes in- and outside Europe. These partnerships provide a large amount of added value, since resources and expertise from these other countries contribute to the outcomes of the KB WOT Fisheries programme. Also, a large part of the KB WOT resources is specifically dedicated to international collaboration and exchange of science. This ensures that Wageningen Marine Research researchers remain at the centre of scientific developments and international fisheries research. The programme was also very productive in terms of publications, presentations and developing new methods or tools for fisheries research. Over 20 international presentations were given at meetings, workshops and symposia, and 24 international and national reports were written. 9 new methods or models were developed, 4 peer reviewed publications published and 1 scientific publication prepared
    Mission report Kenya : scoping Mission Marine Fisheries Kenya
    Hoof, Luc van; Steins, Nathalie A. - \ 2017
    IJmuiden : Wageningen Marine Research (Wageningen Marine Research report C038/17) - 136
    marine fisheries - food security - aquaculture - seaweeds - trade - kenya - zeevisserij - voedselzekerheid - aquacultuur - zeewieren - handel - kenya
    Mission report Tanzania : scoping mission marine fisheries Tanzania
    Hoof, Luc van; Kraan, Marloes - \ 2017
    IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C004/17) - 66
    zeevisserij - visserij - voedselzekerheid - zeewieren - samenwerking - handel - tanzania - marine fisheries - fisheries - food security - seaweeds - cooperation - trade - tanzania
    PMR Monitoring Natuurcompensatie Voordelta-bodemdieren : datarapport campagne bodemschaaf 2015-multivariate analyse 2004-2013
    Craeymeersch, J.A. ; Perdon, J. ; Jol, J. ; Brummelhuis, E.B.M. ; Asch, M. van - \ 2017
    IJmuiden : IMARES Wageningen UR (IMARES rapport C073.16) - 37
    voordelta - bodemarthropoden - bodeminvertebraten - monitoring - gegevensanalyse - zeevisserij - voordelta - soil arthropods - soil invertebrates - monitoring - data analysis - marine fisheries
    Het voorliggende rapport beschrijft de gewijzigde opzet van de monitoring, alsook de eerste monitoring-resultaten d.m.v. een korte beschrijving van de dataset verkregen met de bodemschaaf (omdat de monsters met de box-corer uit 2015 niet tijdig verwerkt waren om in dit rapport opgenomen te worden). Verder wordt de aanvullende studie nader besproken, qua opzet en resultaten van de multivariate analyses.
    Indicatieve impact maatregelen zeebaars : eerste indicatie van de mogelijke impact van zeebaarsbeschermende maatregelen op de Nederlandse zeevisserij
    Strietman, W.J. ; Weegh, J.B.M. op de - \ 2016
    Wageningen : LEI Wageningen UR (Nota / LEI Wageningen UR 2016-007) - 23
    zeebaars - zeevisserij - visserijbeheer - visbestand - bescherming - quota's - milieueffect - nederland - sea bass - marine fisheries - fishery management - fishery resources - protection - quotas - environmental impact - netherlands
    Zeebaars paaigebieden en opgroeigebieden in Nederlandse wateren
    Tulp, I.Y.M. ; Hal, R. van; Damme, C.J.G. van; Smith, S.R. - \ 2016
    IMARES (Rapport / IMARES C060/16) - 35
    visserijbeheer - zeevisserij - visserijbeleid - visbestand - habitatbeheer - nederland - het kanaal (english channel) - kuitschieten - waddenzee - zeeuwse eilanden - boomkorvisserij - zeebaars - noordzee - rijpen - fishery management - marine fisheries - fishery policy - fishery resources - habitat management - netherlands - english channel - spawning - wadden sea - zeeuwse eilanden - beam trawling - sea bass - north sea - maturation
    De zeebaarspopulatie neemt sinds 2010 sterk af door een hoge visserij-inspanning en een lage aanwas van jonge zeebaars sinds 2008. Zeebaars is een langlevende soort die zich pas op latere leeftijd gaat voortplanten. Op een leeftijd van ca 4 jaar en met een lengte vanaf ca 42 cm (vrouwtjes) en 32 cm (mannetjes) beginnen ze paairijp te worden. De huidige minimum aanlandingsmaat van 42 cm heeft als gevolg dat veel vrouwtjes al gevangen worden voordat ze voor het eerst hebben kunnen paaien. Naast vangstbeperkende maatregelen wordt gezocht naar maatregelen ter bescherming van paai- en opgroeigebieden. Hiervoor is ecologische kennis nodig, die voor de Nederlandse wateren nog grotendeels ontbreekt. Aanwezigheid van paaiende volwassen zeebaarzen is direct bewijs voor een paaigebied. Het alternatief is om aan paaigebieden vast te stellen aan de hand van de verspreiding van eieren in een vroeg ontwikkelstadium. Een relatief groot aantal larven en juveniele zeebaars kan wijzen op het belang van een gebied als opgroeigebied. Aanbevelingen voor beleid Gezien de huidige staat van onze kennis, kunnen we nu geen steekhoudende aanbevelingen voor maatregelen gericht op bescherming van gebieden of habitats te geven. De evidentie voor paaigebieden is nog erg dun, de opgroeigebieden zijn wel redelijk bekend, maar over het relatieve belang van elk gebied voor de populatie is nog geen inzicht. Het is duidelijk dat overbevissing een probleem is gezien de ontwikkelingen in de aanlandingen en de afname in gemiddelde lengte bij aanlanding. Het is ook duidelijk dat de zeebaars die in Nederland gevangen wordt in ieder geval voor een groot deel afkomstig is uit het Kanaal en dat de visserij daar in het vroege voorjaar van grote invloed is op de hoeveelheid zeebaars, die later in het jaar in onze wateren terechtkomt. Op basis van de huidige gegevens en inzichten is een verdere inperking van de vangsten door zowel commerciële als recreatieve vissers in ieder geval een effectieve maatregel om de zeebaarsstand te vergroten. Of er in aanvulling daarop ook noodzaak is om gericht gebieden of habitats te beschermen of te verbeteren is met de huidige kennis en gegevens niet vast te stellen en kan alleen met aanvullend onderzoek worden vastgesteld.
    Economic essays on marine invasive species and international fisheries agreements
    Walker, A.N. - \ 2016
    Wageningen University. Promotor(en): Ekko van Ierland, co-promotor(en): Rolf Groeneveld; Hans-Peter Weikard. - Wageningen : Wageningen University - ISBN 9789462576308 - 165
    fisheries - fisheries ecology - agreements - biodiversity - invasive species - europe - marine fisheries - marine fishes - visserij - visserij-ecologie - overeenkomsten - biodiversiteit - invasieve soorten - europa - zeevisserij - zeevissen

    This thesis is divided into two parts, as explained in Chapter 1, which focus on different aspects of marine ecological change. Part A considers marine Invasive Alien Species (IAS), which are taxa introduced outside of their native range. The detrimental consequences of invasions for human welfare necessitate management of IAS. There are two types of IAS management. These are (i) management of the risks that an invasion will become established, termed “prevention”, and (ii) management of already established invasions, termed “control”. Chapter 2 considers prevention of invasive species with Ballast Water Management (BWM). Vessels transport invasive species in their ballast water. BWM involves treating ballast water to reduce the risk of successful invasion establishment. Chapter 2 studies the determinants of optimal ballast water treatment standards from a theoretical perspective. Chapter 3 considers control of already established invasions from a spatial and dynamic perspective. We model a non-native habitat divided into patches, where each patch may contain a population of the invasive species, and where spread of the invasion between patches is a stochastic process. In this context, we derive optimal management policies.

    The second part of this thesis: Part B, considers International Fisheries Agreements (IFAs). IFAs facilitate cooperation in the management of fish stocks. Cooperation is necessary to ensure sustainable management. Part B focuses on two issues which may affect the stability of cooperation within IFAs. These are; in Chapter 4, changes in stock location, which may occur due to climate change, and in Chapter 5, the risk of stock collapse, which may exist due to overfishing. Part B uses game theory to analyse the effects of these two issues on the stability of the Grand Coalition, which is the state of affairs where all parties cooperate to maximize their joint benefit from the fish stock.

    The methods and findings of the thesis are summarized as follows: in Chapter 2 (Part A), we construct a model to study optimal BWM standards. The model is built around the assumption that invasions arriving via ballast water are irreversible, i.e. once an invasion has arrived, it is not possible to reduce the size of the invasive population to zero. The hazard rate of invasion establishment can be reduced by setting a BWM standard. The hazard rate is also affected by the Minimum Viable Population (MVPs) of the species and the possibility of an Allee effect. An MVP exists if there is some population size below which there is an insufficient number of invasive individuals to sustain a population. An Allee effect exists if the probability that a population survives increases at an increasing rate in the size of the population. Our analysis focuses on the conditions under which a BWM standard which aims to reduce invasive populations in ballast water to below their MVPs (as is aimed for by the BWM convention) can be optimal. We find that the current aim of the BWM convention can only be optimal in the case that the hazard function (which determines the hazard rate) is not continuously differentiable around the MVP. We find that Allee effects are a requirement for a continuously differentiable hazard function. Therefore, we find that whether or not an Allee effect exists fundamentally affects whether it is optimal to aim to reduce an invasive population in ballast water to marginally below its MVP.

    In Chapter 3 (Part A), we combine aspects of previous modelling approaches to provide new generalized management insights for controlling established invasions. We employ a metapopulation network consisting of patches which are arranged one-dimensionally (i.e. in a line), which is relevant, among other cases, for invasive species spreading along coastlines. We allow for the population size of the invasion within patches to be reduced, which we term “removal”, and we allow for the probability of spread between patches to be reduced without affecting the population sizes directly, which we term “containment”. We employ numerical stochastic dynamic programming to explore how these two interventions (removal and containment) can be optimally applied to minimize the sum of damages from the invasion and the costs of removing and containing the invasion. We find that allowing for varying stock sizes within patches facilitates optimal timing of the application of containment. We also identify two novel optimal policies: the combination of containment and removal to stop spread between patches and the application of up to four distinct policies for a single patch depending on the size of the invasion in that patch.

    Chapter 4 (Part B) considers how Grand Coalitions can be stabilized in the face of changing stock location. To do so, we employ the Gordon-Schaefer fisheries model. We consider farsightedness as a mechanism by which stability of the Grand Coalition can be increased in the face of changing stock location. Farsightedness allows players to respond to deviations of other players by deviating themselves. This reduces the incentives to leave the Grand Coalition. This is in contrast to shortsightedness, whereby players cannot decide to leave the Grand Coalition in response to such a choice by another player. We begin by modifying the farsightedness concept such that it can be used in games with asymmetric players and transfer payments. We proceed to analyse the modified farsightedness concept in the case where players are symmetric (stock location does not change) in order to identify the properties of the concept in the base case. We find that farsightedness increases Grand Coalition stability with respect to shortsightedness. We proceed to analyse the extent to which farsightedness increases Grand Coalition stability, relative to shortsightedness, as fish stock location changes, using sensitivity analysis. We find that farsightedness increases the stability of the Grand Coalition, but also increases the sensitivity of stability to changes in fish stock location. Thus, for any fish stock location, a Grand Coalition is more likely to be stable if players are farsighted, but shifts between a stable and an unstable Grand Coalition will occur more frequently if players are farsighted.

    In Chapter 5 (Part B), we analyse how the stability of Grand Coalitions is affected by an endogenously determined risk of stock collapse. We do so using the Levhari and Mirman (LM) fisheries model, which is adapted such that there is a risk of stock collapse which increases as the fish stock size decreases. We numerically solve the model and calculate the stability of the Grand Coalition. We find that the effect of an endogenously determined risk of stock collapse depends heavily on the assumptions made regarding how payoffs are determined. A common assumption in the literature is that payoffs are determined at the steady state fish stock. Under this assumption, endogenous risk means that for specific discount and growth rates, a Grand Coalition is stable for any number of players. This is a very different result from the original LM model whereby Grand Coalitions can never be sustained. This is because players can essentially follow two strategies in response to the risk. Firstly, they can attempt to maintain the fish stock by fishing less. In doing so they are running the risk of collapse. Secondly, they can avoid the risk by pre-emptively depleting the fish stock, i.e. harvesting the stock to zero immediately to avoid the risk. Grand Coalitions of any number of players are stable for parameterizations for which a Grand Coalition attempts to maintain a non-zero fish stock and if a deviation from the Grand Coalition would result in pre-emptive depletion. We proceed by relaxing the assumption that payoffs are determined in the steady state by allowing for deviators to obtain payoffs in the transition between steady states. In this case, only Grand Coalitions of two players are stable, and then only for certain parameterizations. The reason is that players can now gain payoffs in the process of pre-emptively depleting the stock, i.e. payoffs are received from the process of fishing the stock down to zero. This increases the benefit of deviating from the Grand Coalition. In this case, Grand Coalitions are only stable for two players for specific parameterizations.

    Chapter 6 summarises the research questions formulated in Chapter 1 and evaluates the work of the thesis. Regarding Chapter 2, we justify our theoretical approach with the following two points. Firstly, BWM management is a global and complex problem, which means that the information required to formally calculate an optimal standard is prohibitively burdensome. Secondly, we argue that the complexity of BWM necessitates a sound theoretical understanding of the problem in order to evaluate the current BWM standard, and also to aid in future policy formulation. Similarly, in Chapter 3, we focus on deriving generalized management insights which are applicable to a variety of real-world cases, as opposed to deriving an optimal management strategy for a specific case. In addition to the data requirements necessary to derive such a management strategy, the complexity of such applied cases leads to potentially excessive computational burden. Chapter 3 analyses systems of two and three patches, which are likely to be too simple to analyse specific real world cases, but are sufficient to derive generalized management insights.

    The game theoretic methodologies in Part B are evaluated principally in terms of the assumptions about changes in stock location in Chapter 4 and the numerical method in Chapter 5. In Chapter 4, the fish stock is conceptualised as existing at a single point in space. The location of this point is determined in relation to fishing nations, which are also conceptualised as single points in space. Changes in stock location result from rises in ocean temperatures due to climate change. Such rises in temperature are likely to lead to other changes in the fish stock such as the size of the area where the fish stock can be found and increases in the maximum fish stock size which the ecosystem can support. These other aspects of changing stock location need to be considered in evaluating Chapter 4, as well as in formulating more applied models. In Chapter 5, a numerical method is adopted to analyse the effects of an endogenous risk of stock collapse. To do so, the utility function in the LM model is adapted such that it can be used in a numerical model. In order to isolate the effect of endogenous risk from changes in the utility function, a validation procedure is carried out by comparing analytically derived results in the deterministic case (without endogenous risk of stock collapse) to numerically derived results in the deterministic case. This reveals that changes to the utility function have a negligible effect and thus the results, in terms of the stability of Grand Coalitions can be attributed solely to endogenous risk of stock collapse.

    Overall, Part A of this thesis presents new insights into the determinants of optimal BWM standards. These insights demonstrate the conditions under which the current BWM standard, which aims to eliminate the risk of invasion establishment, may or may not be optimal. Part A therefore provides a novel theoretical framework which aids in the evaluation of current, and the determination of future standards. Part A also provides new insights into the control of established invasions, by extending existing spatially explicit optimal control models. Specifically, dividing space into patches and allowing for varying invasive population sizes within patches facilitates the optimal timing of management interventions and, in general, more detailed, and thus more efficient, management strategies. Part B provides a novel analysis of the effects of changing stock location on Grand Coalitions by explicitly introducing fish stock location in the analysis, and shows how farsightedness can stabilize Grand Coalitions in the face of such changes. Part B also shows how the effects of an endogenous risk of stock collapse on the stability of Grand Coalitions depends vitally on whether transition payoffs are included. These results can form the basis for more interdisciplinary analyses, analyses of different types of marine ecological change, and analyses of these changes in different settings, such as non-European countries.

    Overleving van discard platvis: vaststellen en verhogen
    Marlen, B. van; Molenaar, P. ; Reijden, K.J. van der; Goudswaard, P.C. ; Bol, R.A. ; Glorius, S.T. ; Theunynck, R. ; Uhlmann, S.S. - \ 2016
    IMARES (Rapport / IMARES C180/15) - 116
    pleuronectiformes - overleving - discards - zeevisserij - visserijbeheer - nederland - pleuronectiformes - survival - discards - marine fisheries - fishery management - netherlands
    On the possibility of RTCs in the Dutch demersal fishery
    Verkempynck, R. ; Machiels, M.A.M. - \ 2016
    IMARES (Report / IMARES C012/16) - 32
    marine fisheries - discards - monitoring - fishery management - netherlands - zeevisserij - discards - monitoring - visserijbeheer - nederland
    VISNED has asked IMARES to do conduct a short feasibility study on the possibility of Real time closures (RTCs) as a tool for the Dutch demersal fishery to cope with the landing obligation (EU regulation 1380/2013). This assignment is part of the EVF-project “Innovatieve discardvermindering in de praktijk” (Innovative discard reduction in practice). In this report we present a short overview of examples of (real time)-closures in Europe. Additionally, known advantages and disadvantages are listed. Next we present discard maps that are based on data from the yearly Dutch discard monitoring and ongoing VIP projects collecting discards. Two sources of data are currently available. We discuss the suitability of these maps and the information they deliver as a driver for a possible RTC system.
    VIP report "Use of new broadband echosounder" : Techniques for improved ocean imaging and selectivity in pelagic fisheries
    Fassler, S.M.M. ; Scoulding, B.C. ; Burggraaf, D. ; Haan, D. de; Quesson, Benoit ; Sande, Jeroen van de; Beerens, Peter - \ 2015
    IMARES (Report / IMARES C171/15) - 100
    pelagic fishery - marine fisheries - underwater acoustics - fish stocks - bycatch - fishery resources - fishery management - pelagische visserij - zeevisserij - onderwaterakoestiek - visstand - bijvangst - visbestand - visserijbeheer
    Impact Assessment of the Flyshoot fishery in Natura 2000 and MSFD areas of the Dutch continental shelf
    Rijnsdorp, A.D. ; Bos, O.G. ; Slijkerman, D.M.E. - \ 2015
    IJmuiden : IMARES (Report / IMARES C162/15) - 24
    marine fisheries - fishing methods - fishing gear - environmental impact - aquatic ecosystems - north sea - netherlands - zeevisserij - vismethoden - vistuig - milieueffect - aquatische ecosystemen - noordzee - nederland
    North Sea Herring and Pelagic Ecosystem Survey (HERAS) report for R/V "TRIDENS" 22 June - 17 July 2015
    Couperus, A.S. ; Fassler, S.M.M. ; Scoulding, B.C. - \ 2015
    IJmuiden : IMARES (Report / IMARES 15.015) - 30
    herrings - surveys - fish stocks - marine fisheries - acoustic tracking - fishery resources - north sea - haringen - karteringen - visstand - zeevisserij - akoestisch sporen - visbestand - noordzee
    Fisheries displacement effects related to closed areas : a literature review of relevant aspects
    Slijkerman, D.M.E. ; Tamis, J.E. - \ 2015
    Den Helder : IMARES (Report / IMARES C170/15) - 51
    marine fisheries - fishing grounds - displacement - environmental protection - socioeconomics - fishery management - north sea - netherlands - zeevisserij - visgronden - verplaatsing - milieubescherming - sociale economie - visserijbeheer - noordzee - nederland
    VIBEG Monitoring T1 in 2015 - Data Deelrapportage
    Goudswaard, P.C. ; Bakker, A.G. ; Asch, M. van; Smith, S.R. ; Weide, B.E. van der; Brummelhuis, E.B.M. ; Cuperus, J. - \ 2015
    Yerseke : IMARES (Rapport / IMARES C172/15) - 24
    natuurbescherming - zeevisserij - zonering - beschermde gebieden - kustgebieden - bemonsteren - noordzee - nederland - nature conservation - marine fisheries - zoning - reserved areas - coastal areas - sampling - north sea - netherlands
    Het ‘VIBEG (Visserij in Beschermde Gebieden) akkoord’ betreft twee Habitat- en Vogelrichtlijngebieden: ‘Noordzeekustzone’ en ‘Vlakte van de Raan’. Het doel van dit akkoord is om de instandhoudingsdoelen te realiseren voor habitattype H1110B en schelpdieretende vogels in het kader van Natura2000, in combinatie met een ecologisch verantwoorde en duurzame visserij in deze gebieden. Om dit doel te bereiken is voor de Noordzeekustzone in december 2011 een zonering ingesteld met verschillende toegangsregels voor de visserij. Om de mogelijke effecten van deze verschillende visserijregimes op het bodemleven te kunnen vaststellen is in 2013 een onderzoeksprogramma opgestart voor benthische organismen en vissen. Met drie verschillende en elkaar aanvullende technieken: boxcorer, bodemschaaf en garnalennet, is in 2013 een eerste bestandsopname (T0) gemaakt op twee locaties in de Noordzeekustzone: Petten en Ameland. In 2015 is een tweede bestandsopname (T1) gemaakt, wederom op de twee locaties in de Noordzeekustzone: Petten en Ameland. In dit rapport worden de resultaten van de bestandsopname in 2015 gepresenteerd. Een vergelijking tussen de data van 2015 en 2013, zoals die gerapporteerd zijn in Goudswaard et al. (2014), zal in een later stadium plaatsvinden.
    VIP Report Acoustic Data Collection
    Fassler, S.M.M. ; Brunel, T.P.A. ; Couperus, A.S. ; Gastauer, S. ; Burggraaf, D. - \ 2015
    IJmuiden : IMARES (Report / IMARES C178/15) - 121
    herrings - whiting - marine fisheries - fish stocks - fishery resources - fishery management - fishing vessels - acoustic tracking - surveys - haringen - wijting - zeevisserij - visstand - visbestand - visserijbeheer - vissersschepen - akoestisch sporen - karteringen
    De vormgeving van beleid in een Multi-level Governance setting - VIP Rapport : Analyse van bijeenkomsten tussen vissers en EZ over de omstreden aanlandplicht 2013, 2014 en 2015
    Trapman, B.K. ; Kraan, M.L. - \ 2015
    IJmuiden : IMARES (Rapport / IMARES C196/15) - 35
    zeevisserij - discards - vis vangen - visserijbeleid - governance - plichten - wetgeving - europa - marine fisheries - discards - fishing - fishery policy - governance - duties - legislation - europe
    VIP HydroRig II
    Marlen, B. van - \ 2015
    IJmuiden : IMARES (Rapport / IMARES C004/15) - 24
    fishing gear - marine fisheries - fishing methods - plaice - fish catches - netherlands - vistuig - zeevisserij - vismethoden - schol - visvangsten - nederland
    Als vervolg op het VIP-project HydroRig I waarbij een vistuig werd ontwikkeld als alternatief voor de boomkor met manipulatie van de waterstroming in het voortuig van het vistuig is in 2013 en 2014 een nieuwe variant HydroRig II beproefd door de firma Geertruida B.V. Dit vistuig had een breedte van 15 m waarvoor ontheffing was verkregen en wielen die de sloffen vervingen. De praktijkproeven lieten een goed vangstresultaat op schol zien in vergelijking met schepen in de buurt vissend met ca. 10% brandstofbesparing. Een gedetailleerde vangstvergelijking is nodig om ecologische voordelen beter te kwantificeren.
    Pelagic fish discards : technical report on opportunities for silage valorisation
    Rurangwa, E. ; Poelman, M. ; Broeze, J. ; Bosch, Heleen van den - \ 2015
    Yerseke : IMARES (Report / IMARES C197/15) - 30
    pelagic fishery - marine fisheries - discards - fish silage - livestock feeding - bioactive compounds - hydrolysis - feed industry - pelagische visserij - zeevisserij - discards - vissilage - veevoeding - bioactieve verbindingen - hydrolyse - veevoederindustrie
    Over het welzijn van in zee gevangen vis
    Jonge, F.H. de; Boon, N. ; Brauner, M. ; Dakriet, N. ; Kumar Ghosh, A. ; Jansen, J. ; Hamoen, J. ; Kok, J. de; Hürlimann, R. ; Laan, R. ; Marbus, S. ; Merema, P. ; Pijcke, N. ; Rooijen, K. van; Stolwijk, D. ; Vissia, S. ; Vrijenhoek, M. ; Willemsma, A. ; Zaalberg, R. ; Zagenia, F. - \ 2015
    Wageningen : Wetenschapswinkel Wageningen UR (Rapport / Wetenschapswinkel Wageningen UR 322) - 57
    dierenwelzijn - vis - wilde dieren - diergezondheid - visserij - zeevisserij - vismethoden - animal welfare - fish - wild animals - animal health - fisheries - marine fisheries - fishing methods
    De Stichting Vissenbescherming heeft de hulp van de wetenschapswinkel van Wageningen UR ingeroepen. Zij vraagt haar te ondersteunen met onderzoek dat een stap voorwaarts kan betekenen op weg naar een vissenwelzijnskeurmerk voor in het wild gevangen (zee)vis. In totaal 19 studenten (3 studententeams en 2 masterstudenten) deden voor de wetenschapswinkel (literatuur)onderzoek naar a) welzijn van vissen (met name platvis) in relatie tot de visserij en b) maatschappelijke agendering op het gebied van vissenwelzijn. Op grond van een literatuurstudie wordt geconcludeerd dat steeds meer wetenschappelijke argumenten erop wijzen dat ook vissen pijn lijden en emoties kunnen ervaren. Voor diegenen die deze argumenten in twijfel trekken wordt door Elder bepleit het “voorzorgsprincipe” te hanteren, waarbij ernaar gestreefd wordt het risico op pijn en leed bij vissen zoveel mogelijk te voorkomen.
    Teveel tong verspeeld, zoektocht gaat verder: IMARES presenteert tussentijdse resultaten project Netinnovatie kottervisserij (interview met Pieke Molenaar)
    Molenaar, P. - \ 2015
    Visserijnieuws 35 (2015)37. - ISSN 1380-5061 - p. 3 - 3.
    zeevisserij - tong (vis) - innovaties - vistuig - demersale visserij - visserijbeheer - marine fisheries - dover soles - innovations - fishing gear - demersal fisheries - fishery management
    Nederlandse kottervissers halen alles uit de kast om selectiever te vissen en zo met het oog op de aanlandplicht discards te sparen. Maar uit de praktijkproeven blijkt dat scheidingspanelen ook een verlies van zo'n tien procent van de tongvangst te betekenen. De zoektocht gaat verder.
    A food web model of invertebrate subtidal soft-bottom communities Part B: effects of fishery
    Schellekens, T. ; Kooten, T. van - \ 2015
    Yerseke : IMARES (Report / IMARES Wageningen UR C131/15) - 21
    zee-invertebraten - voedselwebben - modellen - aquatische gemeenschappen - zeevisserij - visserijbiologie - visserijbeheer - vistuig - natura 2000 - noordzee - marine invertebrates - food webs - models - aquatic communities - marine fisheries - fishery biology - fishery management - fishing gear - natura 2000 - north sea
    Om visserij in de Natura-2000 gebieden Noordzeekustzone en Vlakte van de Raan zodanig te reguleren, dat zij het behalen van de geformuleerde beleidsdoelen niet in de weg staat, is het VIBEG-akkoord gesloten. Kern van de afspraken vormt een ruimtelijke zonering waarmee wordt bepaald welke visserijtechnieken in welke gebieden wel of niet zijn toegestaan.
    A food web model of invertebrate subtidal soft-bottom communities Part A: model derivation and effects of productivity
    Kooten, T. van; Schellekens, T. - \ 2015
    IJmuiden : IMARES (Report / IMARES Wageningen UR C130/15) - 18
    zee-invertebraten - voedselwebben - modellen - aquatische gemeenschappen - zeevisserij - productiviteit - visserijbiologie - vistuig - natura 2000 - noordzee - marine invertebrates - food webs - models - aquatic communities - marine fisheries - productivity - fishery biology - fishing gear - natura 2000 - north sea
    Om visserij in de Natura-2000 gebieden Noordzeekustzone en Vlakte van de Raan zodanig te reguleren, dat zij het behalen van de geformuleerde beleidsdoelen niet in de weg staat, is het VIBEG-akkoord gesloten. Kern van de afspraken vormt een ruimtelijke zonering waarmee wordt bepaald welke visserijtechnieken in welke gebieden wel of niet zijn toegestaan.
    VIP Valorisatie Reststromen Vis (VRV)
    Poelman, M. ; Kals, J. ; Marlen, B. van; Amerongen, A. van; Bosch, H. van den - \ 2015
    IJmuiden : IMARES Wageningen UR (Rapport / IMARES Wageningen UR C005/15) - 67
    vercommercialisering - visresten - visproducten - zeevisserij - pleuronectiformes - visserijbeleid - kosten-batenanalyse - reststromen - commercialization - fish scrap - fish products - marine fisheries - pleuronectiformes - fishery policy - cost benefit analysis - residual streams
    In het kader van de komende aanlandingsplicht van ondermaatse vis is de sector geïnteresseerd in mogelijkheden om deze aanvoer te laten bijdragen tot het inkomen. De vraag werd gesteld welke producten zouden kunnen worden gemaakt uit visafval (snijafval als koppen en staarten en ingewanden en discards). Monsters van dergelijk visafval werden verzameld aan boord van de FD283 van de firma Geertruida B.V. en geanalyseerd in een verscheidenheid van mogelijke verwerkingsprocessen, zowel aan boord (continue en batch hydrolyse met toegevoegde enzymen) als aan de wal (productie van bioactieve peptiden door hydrolyse, productie van vismeel en visolie) door Food and Bio-based Research (FBR) van Wageningen UR en VFC/Lipromar te Cuxhaven.
    Ecosystem effects of bottom trawl fishing
    Denderen, P.D. van - \ 2015
    Wageningen University. Promotor(en): Adriaan Rijnsdorp, co-promotor(en): Tobias van Kooten. - Wageningen : Wageningen University - ISBN 9789462573468 - 182
    vis vangen - zeevisserij - boomkorvisserij - vismethoden - ecosystemen - milieueffect - visserijbeheer - benthos - soortenrijkdom - mariene ecologie - fishing - marine fisheries - beam trawling - fishing methods - ecosystems - environmental impact - fishery management - benthos - species richness - marine ecology - cum laude
    cum laude graduation
    Het kokkelbestand in de Nederlandse kustwateren in 2015
    Asch, M. van; Ende, D. van den; Brummelhuis, E.B.M. ; Zweeden, C. van; Troost, K. - \ 2015
    IJmuiden : IMARES Wageningen UR (Rapport / IMARES Wageningen UR C111/15) - 44
    kokkels - kustwateren - zeevisserij - visserijbeheer - visbestand - visstand - inventarisaties - nederland - natura 2000 - oosterschelde - westerschelde - waddenzee - clams - coastal water - marine fisheries - fishery management - fishery resources - fish stocks - inventories - netherlands - natura 2000 - eastern scheldt - western scheldt - wadden sea
    Onderzoeksinstituut IMARES heeft in opdracht van het ministerie van EZ in het voorjaar van 2015 het kokkelbestand (Cerastoderma edule) in de Waddenzee, de Oosterschelde en de Westerschelde geïnventariseerd. De inventarisatie wordt jaarlijks uitgevoerd om te kunnen bepalen hoeveel er gevist mag worden en is daarnaast ook van belang voor evaluatie van beheersmaatregelen en effectstudies in het kader van Natura 2000 en de natuurbeschermingswet. De kokkelbestandsopname wordt sinds 1990 uitgevoerd in de Oosterschelde en de Waddenzee, sinds 1992 in de Westerschelde en sinds 1993 in de Voordelta (als onderdeel van de bestandsopnamen van mesheften en halfgeknotte strandschelpen in de Nederlandse kustzone). Doel van deze inventarisaties ten behoeve van de visserij is het bepalen van de voorjaarsbestanden in deze gebieden, op basis waarvan een schatting wordt gemaakt van de oogstbare bestanden in september.
    An exploration of potential effects on fisheries and exploited stocks of a network of marine protected areas in the North Sea
    Kooten, T. van; Deerenberg, C.M. ; Jak, R.G. ; Hal, R. van; Machiels, M.A.M. - \ 2015
    IJmuiden : IMARES Wageningen UR (Report / IMARES Wageningen UR C093/14) - 52
    visserijbeleid - zeevisserij - zeereservaten - noordzee - visserijbeheer - fishery policy - marine fisheries - marine protected areas - north sea - fishery management
    WWF Netherlands has developed a proposal for a network of Marine Protected Areas (MPAs) in the North Sea. Most of the MPAs in this network are already protected under the Natura 2000 framework and/or the Marine Strategy Framework Directive. WWF Netherlands aims to engage with stakeholders and build support for this proposed MPA network. One of the most prominent of these stakeholders is the fishing industry. To provide input for the discussion with stakeholders, the current study investigates potential fishery effects of a total fishery ban in each of the marine protected areas. This represents a hypothetical choice to facilitate comparison with existing scientific literature and calculations of quantity and value of catches and does not reflect a proposal for a total fishery closure of the entire network by either IMARES or WWF Netherlands.
    Vallen en opstaan: update overlevingsprojecten ILVO en IMARES (interview met Karin van der Reijden)
    Reijden, K.J. van der - \ 2015
    Visserijnieuws 35 (2015)17. - ISSN 1380-5061 - p. 5 - 5.
    visserijbeleid - visserijbeheer - discards - zeevisserij - wetgeving - eu regelingen - visserij - mortaliteit - visstand - demersale visserij - dierenwelzijn - diergezondheid - fishery policy - fishery management - discards - marine fisheries - legislation - eu regulations - fisheries - mortality - fish stocks - demersal fisheries - animal welfare - animal health
    De Europese aanlandplicht is een feit. De visserijsector vreest een negatieve invloed op de bestanden door een hogere vissterfte. In de wetgeving is een uitzonderingsmaatregel voor de discardban opgenomen als vis een hoge overlevingskans heeft. Zowel in Nederland als België wordt daarom in de kottervisserij wetenschappelijk onderzocht hoe groot de overlevingskansen van gevangen vis zijn. Karin van der Reijden (WUR - IMARES) en Ruben Theunynck (ILVO) geven inzicht in de stand van zaken.
    Van Discards naar Bijvangst in de Pelagische Visserij
    Goudswaard, P.C. - \ 2015
    Yerseke : IMARES (Rapport / IMARES Wageningen UR C067/15) - 27
    visserij - pelagische visserij - discards - bijvangst - zeevisserij - eu regelingen - visserijbeleid - vangstsamenstelling - vis - fisheries - pelagic fishery - discards - bycatch - marine fisheries - eu regulations - fishery policy - catch composition - fish
    De pelagische diepvriestrawler visserij richt zich volledig op vis die geschikt is voor humane consumptie. Per 1 januari 2015 is de pelagische zeevisserij in de Europese wateren geconfronteerd met een verplichting om alle gevangen soorten waarvan een vangst quotum is vastgesteld, aan land te brengen en niets van deze vissoorten over boord te zetten. Dit is de eerste realisatie van een reeks aanlandverplichtingen van vis in het kader van het Europese Gemeenschappelijke Visserij Beleid. De aanlanding van deze visserij zal als gevolg van de aanlandplicht veranderen. In dit deelrapport wordt ingegaan op (i) de omvang en samenstelling van de hoeveelheid vis die onder het voormalige systeem als discards beschouwd wordt en (ii) in de hoeveelheid vis die als basis van mogelijke verwerkingsstappen voor valorisatie gebruikt kunnen worden. Daarnaast wordt een verwachting geschetst van de te verwachten hoeveelheid discards die aangeland moeten gaan worden onder de aanlandverplichting die vanaf 1 januari 2015 van kracht is. Dit geeft inzicht in de mogelijkheden voor industriële benutting van de “discards” die een waarde verhoging ten opzichte van laagwaardige verwerking tot vismeel meebrengt.
    Wettelijk Onderzoek Taken WOT-05 Visserijonderzoek: Beknopte jaarraaportage 2014
    Verver, S.W. - \ 2015
    IJmuiden : Centrum voor Visserijonderzoek (CVO rapport 15.007)
    visserijbeheer - visserijbeleid - visbestand - zeevisserij - aquacultuur - beleidsondersteuning - jaarverslagen - nederlandse wateren - economische evaluatie - fishery management - fishery policy - fishery resources - marine fisheries - aquaculture - policy support - annual reports - dutch waters - economic evaluation
    Deze jaarrapportage informeert het Ministerie van Economisch Zaken (EZ) over het onderzoek dat in 2014 is uitgevoerd binnen het programma WOT-05 Visserijonderzoek van DLO. In dit programma worden wettelijke onderzoekstaken uitgevoerd die betrekking hebben op het beheer van de visserij op zee, in Nederlandse kust- en binnenwateren en in de aquacultuur. De tabellen met financiële informatie in deze rapportage zijn een samenvatting van een uitgebreidere rapportage zoals deze afzonderlijk aan EZ verstrekt wordt door DLO.
    Wettelijk Onderzoek Taken WOT-05 Visserijonderzoek: jaarverslag 2014
    Verver, S.W. - \ 2015
    IJmuiden : Centrum voor Visserijonderzoek (CVO rapport 15.006) - 101
    visserijbeheer - visbestand - aquacultuur - zeevisserij - visserijbeleid - nederlandse wateren - jaarverslagen - beleidsondersteuning - fishery management - fishery resources - aquaculture - marine fisheries - fishery policy - dutch waters - annual reports - policy support
    The programme WOT-05 Fishery Research is carrying out statutory research tasks related to the management of the fishery and aquaculture in the Netherlands. The programme is developed in consultation with the Ministry of Economic Affairs (EZ). This report is a technical report and summarises the progress made in carrying out the work plan of 2014. Fisheries policy makers and managers are dependent on up-to-date information. The aim of this programme is to contribute to the collection of essential data needed for the management of fisheries, fish stocks and aquaculture through sampling programmes in as well marine and inshore areas.
    Methods for integrated use of fisheries research survey information in understanding marine fish population ecology and better management advice : improving methods for evaluation of research survey information under consideration of survey fish detection and catch efficiency
    Nielsen, J.R. - \ 2015
    Wageningen University. Promotor(en): Adriaan Rijnsdorp. - Wageningen : Wageningen University - ISBN 9789462572553 - 187
    zeevisserij - onderzoek - karteringen - visserijbeheer - zeevissen - populatie-ecologie - evaluatie - methodologie - visvangsten - visbestand - visserijbiologie - marine fisheries - research - surveys - fishery management - marine fishes - population ecology - evaluation - methodology - fish catches - fishery resources - fishery biology

    Summary

    The thesis developed and improved methods for the integrated analysis of different types of fishery independent research surveys (trawl surveys, acoustic surveys, hydrographical surveys, and gillnet surveys) to study the distribution, density, abundance, migration and biological population dynamic parameters of marine fish species. The topics in the thesis addressed different combinations of trawl, hydro-acoustic, gillnet, and hydrographical data and application of different survey data analysis methods under consideration of factors influencing the survey catch and detection efficiency. Each topic was investigated in one of more case studies.

    One thesis topic has been to provide more precise estimates of fish distribution and density patterns from survey data (Chapter 2). The 1st case study applied advanced statistical methods to Baltic trawl data and hydro-acoustic survey data in combination with survey sampled hydrographical data to estimate distri­bution and density patterns of juvenile 0-group Baltic cod. These patterns were largely unknown. In the 2nd case study new methodology was developed for analyzing trawl research survey data for Baltic cod and whiting including the corre­la­tion in distribution and density according to space, time, size, and species. The more precise density estimates improve the knowledge of the stock-recruitment relationship of Baltic cod and can improve the Baltic multi-species stock assessment. Furthermore, it will enable more precise marine management and spatial planning involving fish stocks and fisheries in the Baltic Sea. In context of Baltic cod stock assessment, the 3rd case study developed a new method for inter-calibration of trawl survey CPUE data by fish size group exemplified by Baltic cod (and flounder) where the concept of disturbance by one trawl haul in relation to the next have been developed and quantified when calibrating new research survey trawl gears with the former ones. These results have been based on introduction of a new international ICES BITS trawl research survey design.

    A second topic was to improve and develop hydroacoustic research survey methods for more precise detection and discrimination of fish species according to fish size and orientation in the water (Chapter 3). Here, the 4th case study focused on more precise acoustic target strength estimation of juvenile cod, while the 5th case study has focused on acoustic discrimination of juvenile gadoid fish in particular juvenile Baltic cod. This enables more efficient research survey estimation of juvenile cod (gadoid) density patterns to be used in stock recruitment estimates and stock assessment.

    The third topic was to estimate more precisely fish mortality, maturity, and growth parameters for small forage fish species using research survey information (Chapter 4). Associated to this, the 5th case study analysed these population dynamic parameters using trawl survey data taking into account spatial variation. This study provided more precise estimates and deeper understanding of Norway pout mortality, maturity, and growth dynamics. The more precise population dynamic parameters have been implemented in and improved the North Sea Norway pout stock assessment, management advice, management, and long term management plan evaluations.

    The fourth topic was to develop methodology to integrate hydroacoustic, gillnet, and hydro­gra­phi­cal research survey data to investigate pelagic fish migration patterns (Chapter 5). The methods were applied in the 6th case study to evaluate Western Baltic herring feeding and spawning migra­tion based on distribution and density estimates in a narrow over-wintering area of the stock. The more precise information on migration patterns gives better possibility for acoustic monitoring of the full stock abundance in different areas and seasons og the year to be used in stock assessment and marine spatial planning. Also, it increases knowledge on biological interactions and mixing with other stocks and species.  

    In the final synthesis Chapter 6, the thesis reviews relevant analysis methods of research survey data and underlying data distributions, survey design and stratification, trawl survey inter-calibration and standardization, as well as estimation procedures and data processing methods in context of the obtained results and methods developed in the thesis. This is done with focus on survey precision and uncertainty (bias, sources of errors) for trawl and acoustic surveys and factors affecting it.

     

     

     

     

    Dioxines en PCB's in Chinese wolhandkrab
    Kotterman, M.J.J. ; Leeuwen, S.P.J. van; Hoogenboom, L.A.P. - \ 2014
    IJmuiden : IMARES (Rapport / IMARES C120/14) - 36
    krabben (schaaldieren) - dioxinen - polychloorbifenylen - besmetting - toxinen - zeevisserij - crabs - dioxins - polychlorinated biphenyls - contamination - toxins - marine fisheries
    Factsheet: Pulsvisserij
    Quirijns, F.J. ; Turenhout, M.N.J. ; Paijmans, A.J. ; Taal, K. - \ 2014
    pulsvisserij - visserij-ecologie - discards - visvangsten - economische haalbaarheid - vismethoden - boomkorvisserij - zeevisserij - vangstsamenstelling - pulse trawling - fisheries ecology - discards - fish catches - economic viability - fishing methods - beam trawling - marine fisheries - catch composition
    De pulstechniek is relatief nieuw en roept veel vragen op over de mate van duurzaamheid en economische haalbaarheid. Daarom is er in de afgelopen decennia veel onderzoek gedaan naar deze visserijtechniek. Deze factsheet bevat de laatste gegevens over vangsten, discards, ecosysteem-effecten en economische haalbaarheid bij gebruik van puls in de platvisvisserij.
    Wettelijke Onderzoek Taken WOT-05 Visserijonderzoek: Werksafspraken en werkplan 2015
    Verver, S.W. - \ 2014
    IJmuiden : Centrum voor Visserijonderzoek (CVO rapport 14.006)
    visserijbeleid - visserij - zeevisserij - kustwateren - aquacultuur - binnenwateren - visserijbeheer - visstand - bijvangst - statistiek - monitoring - onderzoek - duurzaamheid (sustainability) - recreatieactiviteiten - palingen - schaaldieren - fishery policy - fisheries - marine fisheries - coastal water - aquaculture - inland waters - fishery management - fish stocks - bycatch - statistics - monitoring - research - sustainability - recreational activities - eels - shellfish
    Dit rapport beschrijft het werkplan voor 2015 van cluster WOT-05 Visserijonderzoek van Wageningen UR. Wageningen UR voert voor het Ministerie van Economische Zaken (EZ) een aantal programma’s met Wettelijke Onderzoek Taken (WOT) uit. Binnen WOT-05 worden Wettelijke Onderzoek Taken uitgevoerd die betrekking hebben op het beheer van de visserij op zee, in Nederlandse kust- en binnenwateren en de aquacultuur. Het werkplan is een uitwerking van de Uitvoeringsovereenkomst tussen het Ministerie van EZ en de Stichting Dienst Landbouwkundig Onderzoek (DLO), onderdeel van Wageningen UR, voor diensten vanwege wettelijke taken op het terrein van visserijonderzoek voor de periode 2011-2015. Bij deze uitvoerings-overeenkomst zijn voor deze periode werkafspraken gemaakt welke de basis vormen voor de jaarlijkse werkplannen. Daarnaast zijn in deze overeenkomst afspraken gemaakt over de KennisBasis (KBWOT) die specifiek aan dit programma is gekoppeld.
    Vangsten en discards van de pulsvissers GO48 & SL42
    Reijden, K. van der; Rasenberg, M.M.M. - \ 2014
    IJmuiden : IMARES (Rapport / IMARES 14.IMA0354) - 21
    visserij - zeevisserij - zeevissen - samenstelling - pulsvisserij - discards - monitoren - vangstsamenstelling - fisheries - marine fisheries - marine fishes - composition - pulse trawling - discards - monitors - catch composition
    C. Tanis Jaczn. en Zonen C.V. (GO48) en vof Visserijbedrijf C. en J. Brinkman (SL42) zijn in 2012 overgeschakeld naar de pulsvisserij. Vanuit de regeling ‘Duurzame Ontwikkeling Visserijgebieden’ is subsidie toegekend voor de innovatie van de pulskortuigen van beide schepen. Binnen dit project was afgesproken om een document op te leveren met de discard gegevens van beide schepen, deze notitie. Dit betroffen gegevens van twee rnemersreizen en gegevens van twee monitoringsprojecten, afkomstig uit andere projecten. Zo namen beide schepen deel aan het VIP project ‘Praktijknetwerk Netinnovatie’, waaronder de waarnemersreizen vielen. Daarnaast hebben beide schepen deelgenomen aan een monitorprogramma van IMARES; de SL42 nam deel aan de pulskormonitoring, de GO48 aan de discardmonitoring.
    Notitie over vangsten en discards van de pulsvisserij van de ARM25 / ARM33 / TH6
    Rasenberg, M.M.M. - \ 2014
    IJmuiden : IMARES (Rapport / IMARES 14.IMA0158) - 16
    zeevisserij - visserij - pulsvisserij - monitoring - vangstsamenstelling - benthos - marine fisheries - fisheries - pulse trawling - monitoring - catch composition - benthos
    In 2011 en 2012 zijn Vof Zeevisserijbedrijf C. Caljouw en Zn. (ARM25), Visserijbedrijf Van Belzen vof (ARM33) en Zeevisserijbedrijf Johanna Cornelia K.J. Bout en Zn. cv. (TH6) overgeschakeld naar de pulsvisserij. De drie chepen hebben deelgenomen aan de pulskormonitoring en in dit onderzoek gegevens verzameld over de vangsten en discards van de pulsvisserij. De schepen hebben gedurende het programma wekelijks één mand vangst van én trek op een vaste dag en tijd bemonsterd. De mand vangst werd uitgezocht op schol, tong, kabeljauw, en overige vis waarbij onderscheid werd gemaakt tussen maats en ondermaats en op benthos en debris.
    Governance innovation networks for sustainable tuna
    Miller, A.M.M. - \ 2014
    Wageningen University. Promotor(en): Arthur Mol, co-promotor(en): Simon Bush. - Wageningen : Wageningen University - ISBN 9789462570252 - 194
    tonijn - zeevisserij - governance - duurzaamheid (sustainability) - regelingen - netwerken - innovaties - milieubeleid - tuna - marine fisheries - governance - sustainability - regulations - networks - innovations - environmental policy

    Governance Innovation Networks for Sustainable Tuna

    Alice M.M. Miller

    Tuna fisheries are among the most highly capitalised and valuable fisheries in the world and their exploitation will continue for the foreseeable future. This means the sustainability of tuna stocks is a pressing global issue that has received attention from a wide range of societal actors. The analysis presented in this thesis investigates governance innovation networks to understand how interdependent governance arrangements for production and consumption in the tuna global production networks, steer and shape processes of sustainability innovation.

    The question this research seeks to answer is how do different market- and state-led governance innovations advance the governance of sustainable tuna? Using the analytical lens of global production networks, four different governance innovations for sustainability in tuna fisheries in the Western and Central Pacific Ocean, targeting European and North American markets are examined. More specifically: state-led governance innovations in the West and Central Pacific Ocean both through regional bodies and through the interaction between the EU and the Pacific Islands countries; and market-led innovations through the implementation of private standards for certifying tuna fisheries and the firm-NGO development and implementation of consumer-facing traceability systems.

    The cases in this thesis indicate that the state- and market-led distinction is inadequate for understanding sustainability governance in the tuna global production network. Instead, different efforts to both frame and deal with issues surrounding sustainability in the tuna global production network sees actors produce innovative instruments to influence production and consumption practices and that these instruments interact with each other and with different actors to form actor-instrument arrangements. This interaction leads to a reclassification of actor roles away from their assignation as standard state, market and NGO and in turn, this reclassification presents us with the need to form different concepts of power. Therefore, through governance innovation networks we can understand how the interaction between actors and instruments is reconfiguring global production networks when sustainability moves to the fore.

    Niet perfect, wel bruikbaar: de discardatlas voor de Noordzee komt eraan (interview met Martine Pastoors en Floor Quirijns)
    Pastoors, M.A. ; Quirijns, F.J. - \ 2014
    Visserijnieuws 34 (2014)23. - ISSN 1380-5061 - p. 4 - 4.
    discards - visserijbeheer - zeevisserij - noordzee - visserij - visvangsten - discards - fishery management - marine fisheries - north sea - fisheries - fish catches
    Over hoeveel discards hebben we het nu eigenlijk? Met de aanlandplicht in zicht is die vraag prangerder dan ooit. In 2013 besloten de landen rond de Noordzee om te werken aan een discardatlas voor de Noordzee, met daarin informatie over de discards per visserij en per gebied. Martin Pastoors van de PFA/Redersvereniging en Floor Quirijns van IMARES vertellen over de mogelijkheden en onmogelijkheden van de binnenkort te verschijnen discardatlas.
    Ontwikkeling zeebodemintegriteit op het Friese Front en de Centrale Oestergronden in relatie tot bodemberoerende visserij: Verslag expert workshop
    Jongbloed, R.H. ; Slijkerman, D.M.E. ; Witbaard, R. ; Lavaleye, M.S.S. - \ 2013
    Den Helder : IMARES (Rapport / IMARES Wageningen UR C212/13) - 55
    visserij - zeevisserij - mariene ecologie - bodemecologie - noordzee - kennisoverdracht - inventarisaties - fisheries - marine fisheries - marine ecology - soil ecology - north sea - knowledge transfer - inventories
    Het bodemecosysteem van het diepe, slibrijke, noordelijke deel van het NCP wordt momenteel nog niet beschermd. Dit type ecosysteem is aanwezig in de gebieden het Friese Front en de Centrale Oestergronden. Deze gebieden zijn door het Kabinet aangemerkt als zoekgebieden voor ruimtelijke beschermingsmaatregelen. In dit rapport richten we ons op de vraag: - Wat ontwikkelt zich aan habitatkarakteristieken, en vervolgens aan soorten, als je de gebieden sluit voor bodemberoerende visserij? Deze vraag is uitgediept middels een workshop met tien experts van zes Nederlandse organisaties met expertise op het gebied van o.a. mariene ecologie, geologie, morfologie, processen, taxonomie, Noordzee benthos, en impacts van menselijke activiteiten, waaronder visserij.
    Sea@shore: informational governance in marine spatial conflicts at the North Sea
    Toonen, H.M. - \ 2013
    Wageningen University. Promotor(en): Arthur Mol; Jan van Tatenhove; Han Lindeboom. - Wageningen UR : Wageningen UR - ISBN 9789461737748 - 199
    aquatische ecosystemen - mariene gebieden - natuurbescherming - zeereservaten - governance - noordzee - windenergie - zeevisserij - milieubeleid - aquatic ecosystems - marine areas - nature conservation - marine protected areas - governance - north sea - wind power - marine fisheries - environmental policy

    Oceans and seas seem to be an empty space and untouched wilderness, but are in fact heavily used and exploited by different economic activities which have, to greater or lesser extent, environmental impacts. Attention for marine environmental challenges has grown, and is nowadays captured by views on ecosystem-based management. This builds on the notion that the way forward in marine ecosystem protection is an integrated approach that is place- or area-based (so-called spatial turn) and should use the best available scientific information. This research focuses on this spatial turn in marine governance at the North Sea, one of the busiest seas in the world. More specifically, the emphasis on the informational governance of spatial tensions between nature conservation and economic activities at the North Sea.

    Informational governance points to the growing centrality of informational processes in decision-making around environmental challenges. Information is seen as an indispensable resource to use in resolving such challenges and serves as steering tool in governing sustainability. Information provision through all kind of (online) media means is deliberately aimed at influencing decision-making and fostering change of behaviour. In the marine context, informational governance seems to be a new and promising mode of governance. Facilitated by information and communication technologies, information can connect spatially distant environmental issues to people’s daily lives. However, information is not seen as an unproblematic and neutral object, it is at the centre of struggles and debates in decision-making on resolving spatial and environmental challenges at sea.

    This study analyzes how public and private actors through informational governance (try to) resolve spatial conflicts between economic activities and nature conservation at the North Sea, in order to better understand the centripetal force of information in marine governance. Three research questions are guiding the research:

    How can the centrality of information in the spatial turn in marine governance be conceptualized and analyzed? Which actors are involved in informational governance on marine ecosystem protection and use at the North Sea, and how do they (inter-) act in informational processes? How does informational governance contribute to the solving of spatial conflicts between economic activities and nature conservation at the North Sea?

    Chapter 2 gives an account of the research methodology that underpins the research. It explains that the study draws on a non-radical constructivist and critical realist perspective, and presents the research design used in the study: a qualitative case study approach. The selection of the cases has been based on two different rationales. Two cases were selected as they highlight the role of three main actor groups in informational governance at sea. Two other cases explore informational processes in governance arrangements with regard to a specific spatial conflict between marine ecosystem conservation and use(fisheries and offshore wind power development) . In the study, triangulated data gathering served to strengthen the validity and reliability of the research. The mix of methods employed included document review of research reports, policy documents and online information; semi-structured interviews; and participatory observation in several meetings and conferences. In data analysis, an iterative approach following the theoretical propositions of the research was used.

    In Chapter 3, the marine scaping framework is presented to analyse informational governance on marine ecosystem protection and use. Marine scaping through information follows the morphogenetic approach and combines a focus on conditions structuring informational processes with an agency-based approach. The framework distinguishes three scapes that together form the structure-side: seascape, humanscape and mindscape. Seascape represents the connection between the biophysical specifics of the marine ecosystem and the material features of economic activities that are emplaced in this ecosystem. Humanscape points to human organization in social, political and economic terms. Mindscape brings in the ideational dimension, and refers to discourses, ideas, norms, values and perceptions. In the interplay of humanscape with seascape and mindscape, the connection with agency is made, pointing to the initiatives and interactions between actors who, by means of information, strive for sustainability at the North Sea. To assess whether conditions have changed over time, so- called elaboration is added to the framework. In marine governance, the explicit aim is to strive for a balance between ecosystem protection and use, hence to foster elaboration.

    Chapter 3 illustrates the application of the marine scaping framework by a case study about informational initiatives of eNGO officials who want to push the development of a network of Marine Protected Areas (MPAs) at the North Sea forward, in order to achieve “ecological coherence” in marine conservation on the North Sea. It is indicated how and why officials from environmental non-gouvernmental organizations (eNGOs) carried out extensive science-based studies to inform policy-making. This information remains however footloose, because there was no institutional setting where the specific need for a MPA network was (high) on the agenda, and as such, eNGOs had no opportunity to tap their reports into existing informational processes. At the same time, this case study shows how eNGOs build up their so-called “informational capital”.

    The case study presented in Chapter 4 provides a historical understanding of informational interactions between science and policy in the Dutch MPA site selection. By establishing MPAs, nature conservation gains literally a place on the North Sea map. Following international regulations and treaties, North Sea countries are obliged to take the leading role in the designation process, and to use scientific criteria only, based on biological and ecological information. The chapter shows that information about vulnerable and pristine habitats and sea life that needs to be protected was merely lacking or contested. It becomes evident that ecological , socio-economic and political considerations cannot be easily separated. Scientists and policy-makers dealt with the entanglement of interests by sharing tasks in the informational processes, being both information providers and users. It is found that especially in cases of uncertainties and data gaps, judgment by scientists is best characterized as expert judgment and sometimes even gut feeling. However, it is also highlighted that it is necessary to keep science as impartial as possible, and to overtly communicate what and whose information is used.

    Chapter 5 analyses the role of information in incorporating the habitat impact of bottom touching gear in the certification scheme of the Marine Stewardship Council (MSC). This represents a spatial conflict between one of the oldest maritime activities at the North Sea, (plaice) fisheries, and marine conservation. The global MSC labeling program is probably the most famous example of informational governance on marine ecosystem protection and use, as it is almost 20 years old. It fits in neatly with the ideas of informational governance: scientific information to assess the environmental performance of a fishery clash with information derived from the fishery itself and stakeholders. And at the same time, information about the fisheries' performance (through the logo on a fish product) is brought to consumers who in turn can reward sustainable fisheries through their buying power. This case study indicates how eNGOs use informational capital in the informational struggles . This role became especially evident during the assessment of the first North Sea plaice fishery, when WWF started to negotiate information with fishermen beyond the formal MSC assessment procedure in order to creating so-called ‘no take-zones’. The eNGO made sure that informal interactions were not totally disconnected from the assessment process. According to this case study, the two fisheries who agreed on the spatial measure also tried to get most out of the additional spatial measure that became part of their certification. They took the spatial measure up in their message towards (potential) clients, stating their fisheries go even beyond the high sustainability standards of MSC.

    The case study in Chapter 6 concerns informational processes related to the ecological impacts of an economic newcomer at the North Sea, that is offshore wind energy. The chapter highlights how the sustainability promise of this renewable source appears to be ‘dark green’: offshore wind farms (OWFs) contribute to the mitigation of greenhouse gas emissions and to the protection of certain marine life (benthos, fish and some bird species). Remarkably, the ecological differentiation towards offshore wind power remains unexploited. Powerful actors related to this pro-wind discourse, such as the wind sector and large eNGOs, are hesitant to use the dark green message of offshore wind power. In onshore wind debates, their emphasis is on the dominant ‘pro-wind’ discourse about combating climate change which leaves no room for (nuanced) spatial and ecological concerns. It is however stated that including the ecological merits of OWFs in an (existing) informational governance design would not be very complicated, and allows actors to commonly strive for further differentiation in the European electricity market.

    The last chapter recapitulates the general findings of the research. The conclusions suggest that a broad array of actors is involved in informational processes that relate to marine governance and push for more sustainability at the North Sea. These actors can take up five distinctive roles in informational processes, that of information negotiator, information authority, information manager, information verifier and information mediator. This role division might be established in a formal way, although often there is room for actors to take up different roles, sometimes only temporally or informally. The conclusions also point to the theoretical contribution of this research to the theoretical development of informational governance, most notably the lessons learnt from its application to the marine context. The methodological reflections indicate the generalizability of the findings, which are in this research linked to the development of the marine scaping framework and the empirically informed distinction between the five roles of actors in informational governance. Finally, the concluding chapter highlights opportunities for future research, such as studies of informational governance related to other economic activities at the North Sea or in other parts of the world.


    Oceans and seas seem to be an empty space and untouched wilderness, but are in fact heavily used and exploited by different economic activities which have, to greater or lesser extent, environmental impacts. Attention for marine environmental challenges has grown, and is nowadays captured by views on ecosystem-based management. This builds on the notion that the way forward in marine ecosystem protection is an integrated approach that is place- or area-based (so-called spatial turn) and should use the best available scientific information. This research focuses on this spatial turn in marine governance at the North Sea, one of the busiest seas in the world. More specifically, the emphasis on the informational governance of spatial tensions between nature conservation and economic activities at the North Sea.

    Informational governance points to the growing centrality of informational processes in decision-making around environmental challenges. Information is seen as an indispensable resource to use in resolving such challenges and serves as steering tool in governing sustainability. Information provision through all kind of (online) media means is deliberately aimed at influencing decision-making and fostering change of behaviour. In the marine context, informational governance seems to be a new and promising mode of governance. Facilitated by information and communication technologies, information can connect spatially distant environmental issues to people’s daily lives. However, information is not seen as an unproblematic and neutral object, it is at the centre of struggles and debates in decision-making on resolving spatial and environmental challenges at sea.

    This study analyzes how public and private actors through informational governance (try to) resolve spatial conflicts between economic activities and nature conservation at the North Sea, in order to better understand the centripetal force of information in marine governance. Three research questions are guiding the research:

    How can the centrality of information in the spatial turn in marine governance be conceptualized and analyzed? Which actors are involved in informational governance on marine ecosystem protection and use at the North Sea, and how do they (inter-) act in informational processes? How does informational governance contribute to the solving of spatial conflicts between economic activities and nature conservation at the North Sea?

    Chapter 2 gives an account of the research methodology that underpins the research. It explains that the study draws on a non-radical constructivist and critical realist perspective, and presents the research design used in the study: a qualitative case study approach. The selection of the cases has been based on two different rationales. Two cases were selected as they highlight the role of three main actor groups in informational governance at sea. Two other cases explore informational processes in governance arrangements with regard to a specific spatial conflict between marine ecosystem conservation and use(fisheries and offshore wind power development) . In the study, triangulated data gathering served to strengthen the validity and reliability of the research. The mix of methods employed included document review of research reports, policy documents and online information; semi-structured interviews; and participatory observation in several meetings and conferences. In data analysis, an iterative approach following the theoretical propositions of the research was used.

    In Chapter 3, the marine scaping framework is presented to analyse informational governance on marine ecosystem protection and use. Marine scaping through information follows the morphogenetic approach and combines a focus on conditions structuring informational processes with an agency-based approach. The framework distinguishes three scapes that together form the structure-side: seascape, humanscape and mindscape. Seascape represents the connection between the biophysical specifics of the marine ecosystem and the material features of economic activities that are emplaced in this ecosystem. Humanscape points to human organization in social, political and economic terms. Mindscape brings in the ideational dimension, and refers to discourses, ideas, norms, values and perceptions. In the interplay of humanscape with seascape and mindscape, the connection with agency is made, pointing to the initiatives and interactions between actors who, by means of information, strive for sustainability at the North Sea. To assess whether conditions have changed over time, so- called elaboration is added to the framework. In marine governance, the explicit aim is to strive for a balance between ecosystem protection and use, hence to foster elaboration.

    Chapter 3 illustrates the application of the marine scaping framework by a case study about informational initiatives of eNGO officials who want to push the development of a network of Marine Protected Areas (MPAs) at the North Sea forward, in order to achieve “ecological coherence” in marine conservation on the North Sea. It is indicated how and why officials from environmental non-gouvernmental organizations (eNGOs) carried out extensive science-based studies to inform policy-making. This information remains however footloose, because there was no institutional setting where the specific need for a MPA network was (high) on the agenda, and as such, eNGOs had no opportunity to tap their reports into existing informational processes. At the same time, this case study shows how eNGOs build up their so-called “informational capital”.

    The case study presented in Chapter 4 provides a historical understanding of informational interactions between science and policy in the Dutch MPA site selection. By establishing MPAs, nature conservation gains literally a place on the North Sea map. Following international regulations and treaties, North Sea countries are obliged to take the leading role in the designation process, and to use scientific criteria only, based on biological and ecological information. The chapter shows that information about vulnerable and pristine habitats and sea life that needs to be protected was merely lacking or contested. It becomes evident that ecological , socio-economic and political considerations cannot be easily separated. Scientists and policy-makers dealt with the entanglement of interests by sharing tasks in the informational processes, being both information providers and users. It is found that especially in cases of uncertainties and data gaps, judgment by scientists is best characterized as expert judgment and sometimes even gut feeling. However, it is also highlighted that it is necessary to keep science as impartial as possible, and to overtly communicate what and whose information is used.

    Chapter 5 analyses the role of information in incorporating the habitat impact of bottom touching gear in the certification scheme of the Marine Stewardship Council (MSC). This represents a spatial conflict between one of the oldest maritime activities at the North Sea, (plaice) fisheries, and marine conservation. The global MSC labeling program is probably the most famous example of informational governance on marine ecosystem protection and use, as it is almost 20 years old. It fits in neatly with the ideas of informational governance: scientific information to assess the environmental performance of a fishery clash with information derived from the fishery itself and stakeholders. And at the same time, information about the fisheries' performance (through the logo on a fish product) is brought to consumers who in turn can reward sustainable fisheries through their buying power. This case study indicates how eNGOs use informational capital in the informational struggles . This role became especially evident during the assessment of the first North Sea plaice fishery, when WWF started to negotiate information with fishermen beyond the formal MSC assessment procedure in order to creating so-called ‘no take-zones’. The eNGO made sure that informal interactions were not totally disconnected from the assessment process. According to this case study, the two fisheries who agreed on the spatial measure also tried to get most out of the additional spatial measure that became part of their certification. They took the spatial measure up in their message towards (potential) clients, stating their fisheries go even beyond the high sustainability standards of MSC.

    The case study in Chapter 6 concerns informational processes related to the ecological impacts of an economic newcomer at the North Sea, that is offshore wind energy. The chapter highlights how the sustainability promise of this renewable source appears to be ‘dark green’: offshore wind farms (OWFs) contribute to the mitigation of greenhouse gas emissions and to the protection of certain marine life (benthos, fish and some bird species). Remarkably, the ecological differentiation towards offshore wind power remains unexploited. Powerful actors related to this pro-wind discourse, such as the wind sector and large eNGOs, are hesitant to use the dark green message of offshore wind power. In onshore wind debates, their emphasis is on the dominant ‘pro-wind’ discourse about combating climate change which leaves no room for (nuanced) spatial and ecological concerns. It is however stated that including the ecological merits of OWFs in an (existing) informational governance design would not be very complicated, and allows actors to commonly strive for further differentiation in the European electricity market.

    The last chapter recapitulates the general findings of the research. The conclusions suggest that a broad array of actors is involved in informational processes that relate to marine governance and push for more sustainability at the North Sea. These actors can take up five distinctive roles in informational processes, that of information negotiator, information authority, information manager, information verifier and information mediator. This role division might be established in a formal way, although often there is room for actors to take up different roles, sometimes only temporally or informally. The conclusions also point to the theoretical contribution of this research to the theoretical development of informational governance, most notably the lessons learnt from its application to the marine context. The methodological reflections indicate the generalizability of the findings, which are in this research linked to the development of the marine scaping framework and the empirically informed distinction between the five roles of actors in informational governance. Finally, the concluding chapter highlights opportunities for future research, such as studies of informational governance related to other economic activities at the North Sea or in other parts of the world.

    Scheidingspaneel in platvisvisserij toont hoopvolle resultaten: pulskotter met paneel kan 65 procent minder discards vangen dan bokker met wekkerketting (interview met Bob van Marlen)
    Marlen, B. van - \ 2013
    Visserijnieuws 33 (2013)45. - ISSN 1380-5061 - p. 7 - 7.
    boomkorvisserij - pulsvisserij - zeevisserij - pleuronectiformes - discards - beam trawling - pulse trawling - marine fisheries - pleuronectiformes - discards
    Het aanbrengen van scheidingspanelen in boomkor- en pulskornetten biedt hoopvolle resultaten om de hoeveelheid discards te reduceren. Dat blijkt uit praktijkonderzoek afgelopen zomer op de TX 68 en UK 45. Vissers zelf spraken over discardreducties tot dertig procent. IMARES heeft de wetenschappelijke rapportage bijna afgerond en komt op verschillen van 15 procent bij de Texelse pulsvisser en 25 procent bij de Urker bokker. Een verslag van projectmanager Bob van Marlen (IMARES) in samenspraak met de schippers Cor Daalder, Pieter Aris van der Vis en Jelle Hakvoort. In vergelijking tot een bokker met wekkerketting noemt Van Marlen een reductie van circa 65 procent mogelijk met een pulskotter met panelen.
    Noordzeevissers verkopen hun vis zelf via internet : VersvandeVisser.nl
    Eijk, H. van; Wubben, R. ; Taal, C. - \ 2013
    Utrecht : InnovatieNetwerk (Rapport / Innovatienetwerk 13.2.318) - ISBN 9789050595025 - 71
    vis - markten - zeevisserij - zeevissen - handel - internet - logistiek - fish - markets - marine fisheries - marine fishes - trade - internet - logistics
    Vissers kunnen via internet, met een eigen ‘webmarket’, een aanzienlijk hogere omzet en een hogere marge per kilogram vis realiseren in vergelijking met de bestaande verkoopmethode via de visafslag. Met deze nieuwe afzetmogelijkheid in de keten voeren de vissers zelf de regie. De directe relatie met de klant die zo wordt gecreëerd, stelt de visser in staat om meer klantgericht te gaan opereren. De in dit rapport kort uitgewerkte businesscase, webmarket “VersvandeVisser.nl”, verschaft Nederlandse Noordzeevissers inzicht 2 in de rollen, kosten en opbrengsten per ketenschakel. Hiermee is inzichtelijk gemaakt waar mogelijkheden voor vissers liggen om zelf binnen de keten een grotere rol te spelen in het vermarkten van duurzaam gevangen vis, waardoor betere opbrengsten kunnen worden gerealiseerd. Door aan te sluiten op een al opgezette webmarkettool, ’VersvandeKweker.nl’, zou in samenwerking met de visafslag in Scheveningen (UFA, United Fish Auctions) en andere partijen, een pilot moeten worden gestart om rechtstreeks (via internet) verse vis en garnalen aan consumenten en zakelijke klanten te verkopen.
    Nederlanders discussiëren mee met Britten : grootschalige brainstormsessie in Brixham over duurzame visserijtoekomst
    Taal, C. - \ 2013
    Visserijnieuws 33 (2013)32. - ISSN 1380-5061 - p. 6 - 7.
    visserij - zeevisserij - duurzaamheid (sustainability) - kennisoverdracht - kennis - groot-brittannië - fisheries - marine fisheries - sustainability - knowledge transfer - knowledge - great britain
    Wat moet de Britse visserij doen en laten voor een duurzame visserijtoekomst? Het Britse Seafish organiseerde over deze vraag vorige maand in samenwerking met de Prince Charles Charity Foundation en de International Sustainability Unit (ISU) een nationale brainstormsessie. Vanuit Nederland waren Kees Taal (LEI, Wageningen UR), Pieter Louwe van Slooten (UK 153 en UK 148), Louwe de Boer (Ekofish Group) en Marieke Verweij (Prosea) uitgenodigd om mee te discussiëren. Taal schreef een verslag.
    Pilot:"collecting Marine ligtter during regular fish surveys
    Hal, R. van; Vries, M. de - \ 2013
    IJmuiden : IMARES (Report / IMARES Wageningen UR C112/13) - 30
    vaste afvalstoffen - zeevisserij - visserij - inventarisaties - noordzee - solid wastes - marine fisheries - fisheries - inventories - north sea
    This report presents the results of a pilot to monitor marine litter on the sea-floor using regular bottom trawl fish surveys. In the last years registration of marine litter became common practice on some international bottom trawl fish surveys, however it was implemented differently on the participating international vessels. The pilot study gave special attention to the registration of litter caught during the Dutch IBTS Q1 in 2013. This meant that the catch was searched with more detail, the net on the deck was inspected and cleaned, descriptions of each item were given and photos were taken.
    Discards monitoring in the Gillnet Sole Fishery
    Quirijns, F.J. - \ 2012
    [S.l.] : S.n. - 6
    tong (vis) - visserij - zeevisserij - vis vangen - netten - discards - bijvangst - monitoring - dover soles - fisheries - marine fisheries - fishing - nets - discards - bycatch - monitoring
    The Gillnet Sole Fishery Study Group monitored discards since 2011. This document describes results from the self-sampling. No observer trips in the Dutch Sole Gillnet Fishing have taken place under the EU data collection framework (DCF). Under the DCF The Netherlands are obliged to sample ten gill net fishing trips. However, it is not specified which type of gill net fishing trips should be sampled, i.e. no target species is specified. In 2011 observers only went on board gill net trips in which cod was targeted. In 2012, up to November 2012, no observer trips were carried out in these fisheries
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