62 research outputs found
Jack-Mackerel stock assessment simulation
IMARES has been tasked to perform an ICA assessment on a simulated Jack Mackerel dataset. This in order to provide management advice within the SPRFMO framework. The results of the assessments are only briefly discussed, as the Assessment Simulation Task Team mainly focused on agreeing on the underlying simulated dataset and assessment settings during the 8th SPRFMO meeting in Auckland, New Zealand. The summarized outcome of these discussions was that more realistic characteristics of the real fishery and surveys should be incorporated into the simulated dataset. This has been communicated to the designer of the dataset and will result in a revised dataset. CVO (Centrum voor Visserij Onderzoek) has proposed to include the SPRFMO work in the near future into WOT tasks (Wettelijke Onderzoeks Taken). Early 2010 another meeting will be organized in which the Assessment Simulation Task Team will discuss the revised simulated datasets, discuss general assessment settings, perform assessments, compare and discuss these results. The results as listed in this report will be used within these discussions
Additional Request On North Sea Herring Long Term Management Plan Evaluation
Under the current Long Term Management Plan of North Sea herring the stakeholders are concerned that the inter-annual TAC constraint is preventing the stock from being exploited at the maximum sustainable yield. Therefore, ICES was requested by the EU and Norway to evaluate, by 31 October 2011, the impact on the performance of the plan in relation to the objectives of providing sustainable fisheries with stable yield in conformity with the precautionary approach under different harvest control rule
Investigating the possibility of North Sea Herring spawning stock biomass rebuilding within a short timeframe
The potential for the rebuilding of the North Sea herring spawning biomass to above precautionary limit biomass reference points (1.3 million tonnes) was explored by a short term forecast applying different recruitment trends and productivities and the current management agreement between the EU and Norway. This was carried out, so that the PFA could consider rebuilding the herring stock to above 1.3 million tonnes
Investigation into fishing activity near offshore piplines
On the North Sea bottom lie numerous pipelines to link oil- or gas offshore drilling units, - platforms and processing stations on land. Although pipeline tubes are coated and covered with protective layers, the pipelines risk being damaged through man-made hazards like anchor dropping and fishing activities with bottom trawls. This study provides, as a proof of concept, a map of fishing intensities in a buffer area around the pipelines that can be used in a GIS application by Fugro to assess risks and advise TAQA Energy B.V. on e.g. additional survey activities. The addition of a fishing intensity layer to the procedure currently applied by Fugro may improve the overall risk assessment for pipeline damages
Effect van de maaswijdte op de vangstsamenstelling in de boomkorvisserij
Naar aanleiding van discussies over het verhogen van de minimum maaswijdte in de boomkorvisserij van 80 naar 90 mm, is het Productschap Vis in samenwerking met Wageningen IMARES het maaswijdteonderzoek gestart. Met dit onderzoek wilde de sector aantonen dat een verhoging van de maaswijdte naar 90 mm zou leiden tot verlies van maatse tong, terwijl de scholdiscards niet noemenswaardig zouden afnemen. Naast het vergelijken van de vangstsamenstelling, zijn ook analyses gedaan om de selectiviteitsparameters voor tong en schol te toetsen. Helaas was het met de gegevens die zijn verzameld niet mogelijk de selectiefactoren zoals ze nu gebruikt worden te toetsen, doordat de aantallen kleine vissen in de verschillende maaswijdtes te dicht bij elkaar lagen
Towards abundance estimates for jack mackerel in the South Pacific based on acoustic data collected by the commercial vessels
Pelagic trawlers make intensive use of echosounders and therefore could potentially be used as acoustic data collection platforms. This project investigated the possibility of collecting acoustic data and its potential utility to estimate fish stock biomass. The scope of the project was to develop and - when possible - test the tools that would be necessary for large scale data collection from commercial vessels, and investigate the suitability of acoustic data to derive abundance indices
Kernbegrippen visserijbeheer en overzicht toestand visbestanden in Europa
Dit rapport informeert over de biologische achtergronden van het Europese visserijbeleid en over de visbestanden waarop dat beleid van toepassing is. Van de belangrijkste bestanden per ecoregio, zoals Noordzee en Oostzee, is weergegeven hoe groot de paaistand en de visserijdruk zijn
A collaborative approach to mapping value of fisheries resources in the North Sea (Part 1: Methodology)
IMARES and LEI are both contracted on occasion to perform VMS-analyses to produce maps of fishing activity or economic value of fisheries in particular area(s) in the North Sea. Until present, IMARES and LEI use their own methodology which is inspired mostly on their own unique data availabilities which may lead to different results. This in turn may lead to questioning of these methodologies and results, especially in relation to estimations of economic value. The aim of the current study is to compare both methodologies by IMARES and LEI en decide upon a common (unique) methodology for producing fishing activity and value maps and estimating economic value of specific areas. The current report describes the jointly agreed methodology between scientists from IMARES and LEI, using input from the fishing industry. This methodology can be readily applied in future projects aimed at describing the value of particular areas in the North Sea in terms of fishing activity. A secondary aim - included on request of the Dutch Fish Product Board (PVIS) - is to address the question of how IMARES and/or LEI can make use of knowledge of the fishing industry in VMS mapping projects
Nadere effecten analyse staandwantvisserij - bruinvis in Natura 2000 gebied Noordzeekustzone
In de Nadere Effecten Analyse (NEA), opgesteld in het kader van het Natura 2000-beheerplan Noordzeekustzone (NZKZ), is de staandwantvisserij in de NZKZ in 2011 getoetst aan de instandhoudingsdoelstelling van de bruinvis in dit gebied
Nadere effecten analyse staandwantvisserij - bruinvis in Natura 2000 gebied vlakte van de Raan
In de Nadere Effecten Analyse (NEA), opgesteld in het kader van het Natura 2000-beheerplan Vlakte van de Raan (VvdR), is de staandwantvisserij in de Vlakte van de Raan getoetst aan de instandhoudingsdoelstellingen. Een van die doelstellingen betreft die voor de bruinvis. De NEA in dit rapport heeft tot doel kennishiaten in te vullen en hiermee opnieuw een nadere effectenanalyse voor de bruinvis uit te voeren
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