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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Reproductive adaptations to reduce locomotor costs in viviparous fish (Poeciliidae)
Fleuren, Mike - \ 2017
University. Promotor(en): Johan van Leeuwen, co-promotor(en): Bart Pollux. - Wageningen : Wageningen University - ISBN 9789463438025 - 204
fishes - poeciliidae - reproduction - adaptation - vivipary - locomotion - biomechanics - zoology - vissen - voortplanting - adaptatie - levendbarend - voortbeweging - biomechanica - zoölogie

Viviparity, a live-bearing mode of reproduction, has evolved over 100 times independently in vertebrate animals. Despite its frequent evolution, viviparity has a number of hypothesised disadvantages compared to the ancestral mode of reproduction, oviparity (egg-laying). One of these disadvantages is a reduction in locomotor performance during pregnancy, the period of internal development of the embryos. Adaptations to a live-bearing reproductive mode could have evolved to reduce these locomotor costs. In this thesis, I aim to find whether matrotrophy, post-fertilization nutrient provisioning (e.g. through a placental structure), and superfetation, the presence of multiple broods of different developmental stages, reduce the locomotor performance decline during pregnancy in the Poeciliidae, live-bearing fishes.

In Chapter 2, we review the literature on the effects of pregnancy on morphology, performance and fitness. The biomechanics of each mode of locomotion (walking, swimming or flying) are distinct, and are affected differently by the added mass and volume of pregnancy. Furthermore, we list the possible adaptations that have evolved to reduce the locomotor costs of pregnancy, and divide them into three different categories: adaptations that reduce the locomotor costs of live-bearing, adaptations with which the locomotor costs of live-bearing are avoided, and adaptations to the life history of the animal. Lastly, we discuss hiatuses in the literature and experimental procedures to quantify the hypothesised benefit of adaptations.

In Chapter 3, we compare the morphological changes during pregnancy in two closely-related species of live-bearing fish: Poeciliopsis turneri and Poeciliopsis gracilis. These species mainly differ in their mode of nutrient provisioning: P. gracilis is lecithotrophic and P. turneri is an extensive matrotroph. We tracked the morphological changes in 3D using a non-invasive method that creates three-dimensional body models. We find that P. turneri is more slender during the early stages of pregnancy, but increase in size more rapidly. This is in line with the locomotor costs hypothesis, which predicts that matrotrophic fish are more slender during the early stages of pregnancy, but that the difference between the body shapes of lecithotrophic and matrotrophic fish diminishes as pregnancy progresses. Our results indicate that matrotrophy could indeed provide a morphological advantage during pregnancy.

Fast-start performance, a manoeuvre fish deploy to escape predatory strikes, is important for individual survival. In Chapter 4, we use state-of-the-art biomechanical methods to, for the first time, quantify this manoeuvre in three-dimensional space in adult fish (Heterandria formosa). We show that fish can orient their escapes in up- and downwards direction, and that this is correlated with a change in pitch angle of the body. Changes in roll angle of the body were not correlated with orientation of the fish. We furthermore demonstrate that stage 1 of the fast start, often described as a preparatory stage, can already contribute to propulsion. The results from Chapter 4 indicate that three-dimensional measurements of fast-start manoeuvres provide novel insights that were often overlooked.

Measuring fast starts in three-dimensional space is relevant in determining the adverse effects of pregnancy on locomotor performance. We did this by comparing three species of live-bearing fish: P. turneri, H. formosa and Phalloptychus januarius. In Chapter 5, we show that pregnancy-induced changes in abdominal width are correlated with a reduction in performance in the horizontal plane (maximal horizontal speed, change in yaw angle), but less so in the vertical plane (maximal vertical speed, change in pitch angle). Furthermore, we demonstrate that an increase in abdominal width is correlated with a decrease in abdominal curvature and, for some species, in a decrease in maximal curvature rate in the abdomen. Lastly, we show that the pregnancy-induced morphological changes depend on the level of superfetation: species with a high level of superfetation experience higher frequency, but smaller amplitude changes in the shape of the abdomen. Whether superfetation actually results in a more slender body shape, as predicted by the locomotor costs hypothesis, depends on the level of reproductive investment.

In this thesis, I show that pregnancy induces changes in morphology which comes with a cost in fast-start performance. Both matrotrophy and superfetation affect how body shape changes due to pregnancy, but whether the latter provides beneficial changes depends on the level of reproductive investment. Furthermore, I reveal that fast starts can have a substantial three-dimensional component which is relevant both to biomechanicists that aim to understand the physical and physiological mechanisms underlying this manoeuvre and to evolutionary biologists that strive to answer performance-related questions.

Waardekaarten van: Haisborough, Hammond & Winterton, North Norfolk Sandbanks & Saturn Reef
Hintzen, N.T. - \ 2017
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C009/17) - 18 p.
vissen - visserij - waarden - kaarten - natura 2000 - groot-brittannië - kustgebieden - fishes - fisheries - values - maps - great britain - coastal areas
Langs de Engelse kust staan een aantal gebieden op de UK Natura 2000 agenda voor sluiting voor de Nederlandse demersale vloot. Wageningen Marine Research bestudeerde in hoeverre de Nederlandse vloot actief was in dit gebied en hoe de voorgenomen te sluiten gebieden overlappen met voor de visserij interessante visgronden. Een grotere opbrengst (factor 3) wordt gehaald uit het North Norfolk Sandbanks & Saturn Reef gebied (dit is één gebied) ten opzichte van het Haisborough, Hammond and Winterton gebied (dit is ook één gebied). Vooral tong word in dit eerste gebied gevangen terwijl scholvangsten groter zijn in het tweede gebied. De voornaamste visgronden die interessant zijn voor de Nederlandse sector zijn niet opgenomen in de voorgenomen te sluiten gebieden, waarbij juist voor de visserij interessante delen van de totale zoekgebieden niet aangemerkt zijn als te sluiten gebied.
Dieren: waarom heb jij minder medelijden met een vis dan met een varken?
Bovenkerk, Bernice - \ 2017
animal welfare - fishes - animal ethics - wild animals

Niemand vindt het raar dat een vis met kop en al in de supermarkt ligt, terwijl we liever geen varken met kop en al zien liggen. Als vegetariër, is het heel geoorloofd om nog wel vis te eten. Blijkbaar zien wij vissen niet als volwaardige dieren. Onterecht, zegt Bernice Bovenkerk (Wageningen University). Er zijn namelijk steeds meer aanwijzingen dat vissen ontzettend slimme dieren zijn.

Inspanningsadviezen voor snoekbaars, baars, blankvoorn en brasem in het IJssel-/Markermeer : visseizoen 2017/2018
Tiën, Nicola ; Hammen, Tessa van der; Vries, Pepijn de; Schram, Edward ; Steenbergen, Josien - \ 2017
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C018/17) - 79
snoekbaars - baars - rutilus rutilus - abramis brama - vissen - visserij - visstand - ijsselmeer - pike perch - bass - fishes - fisheries - fish stocks - lake ijssel
Het Ministerie van Economische Zaken wil komen tot wetenschappelijk onderbouwd duurzaam beheer van snoekbaars, baars, blankvoorn en brasem in het IJsselmeer en Markermeer. Voor alle vier bestanden is de beleidsdoelstelling voor visseizoen 2017/2018 geformuleerd in het document “Toekomstbeeld visstand IJsselmeer/Markermeer – synthesedocument’. Hierin wordt in ieder geval gestreefd naar ‘een evenwichtiger lengte-opbouw van de bestanden met meer grotere exemplaren en een groter aantal jaarklassen’, als ook ‘een toename van de (paai)bestanden’. Voor het behalen van deze beleidsdoelstellingen zijn inspanningsadviezen gevraagd over de staandwantvisserij en de zegenvisserij, gecombineerd voor het IJsselmeer en Markermeer.
Fish migration river monitoring plan : Monitoring program on the effectiveness of the FMR at Kornwerderzand
Griffioen, A.B. ; Winter, H.V. - \ 2017
IJmuiden : Wageningen Marine Research (Wageningen Marine Research report C012/17A) - 50
fish migration - fishes - habitats - monitoring - afsluitdijk - wadden sea - lake ijssel - vismigratie - vissen - waddenzee - ijsselmeer
This report drafts a monitoring program aiming at determining and optimizing the effectiveness of restoring fish migration at Kornwerderzand with the ‘Fish Migration River’ (FMR.) For an adaptive management of the operation of the FMR, monitoring and evaluation are key aspects. The main research questions underlying the monitoring program will be outlined. The proposed research and monitoring approach describes which monitoring techniques can be applied, what set-up and schedule of different research components involved.
Toestand vis en visserij in de zoete Rijkswateren 2015 : Deel I : Trends
Graaf, M. de; Boois, I.J. de; Bos, O.G. ; Griffioen, A.B. ; Keeken, O. van; Tien, N.S.H. ; Vries, P. de - \ 2016
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C114/16) - 79
vissen - visserij - zoetwaterecologie - monitoring - fishes - fisheries - freshwater ecology
Het rapport “Toestand Vis en Visserij in de Zoete Rijkswateren” bestaat uit drie verschillende delen: Deel I “Trends”, Deel II “Methoden” en Deel III “Data”. In dit rapport (Deel I) worden (i) de trends in commercieel benutte vissoorten per VBC gebied, (ii) de trends in niet-inheemse vissoorten (exoten) en (iii) de trends in ecologische kwaliteitsratio’s vis gerapporteerd. Hiervoor is gebruik gemaakt van de gegevens die binnen de verschillende vismonitoringsprogramma’s op de Zoete Rijkswateren worden verzameld, aangevuld met gegevens over bv. aanlandingen. In de rapportage zijn trendanalyses voor de verschillende commercieel benutte vissoorten en niet-inheemse vissoorten (exoten) gemaakt aan de hand van de beschikbare monitoringsgegevens. De gegevens van deze monitoringsprogramma’s worden gebruikt als indicatoren voor de ontwikkeling van de bestanden van de geanalyseerde soorten over verschillende tijdsperioden. Het rapport concentreert zich op het weergeven van data en trends.
Aquaculture Innovation in Vietnam
Rurangwa, E. ; Baumgartner, U. ; Nguyen, H.M. ; Vis, J.W. van de - \ 2016
Yerseke : Wageningen Marine Research (Wageningen Marine Research report C097/16) - 28
aquaculture - innovations - tilapia - fishes - shrimps - crabs - vietnam - aquacultuur - innovaties - vissen - garnalen - krabben (schaaldieren)
Improving sustainability of striped catfish (Pangasianodon hypophthalmus) farming in the Mekong Delta, Vietnam through recirculation technology
Nguyen, Nhut - \ 2016
University. Promotor(en): Johan Verreth, co-promotor(en): Marc Verdegem. - Wageningen : Wageningen University - ISBN 9789462579194 - 180
fish culture - recirculating aquaculture systems - aquaculture - fishes - nutrients - vietnam - visteelt - recirculatie aquacultuur systemen - aquacultuur - vissen - voedingsstoffen

The aim of this thesis was to document improvements in sustainability indicators of striped catfish (Pangasianodon hypophthalmus, Sauvage, 1878) production through the application of recirculation and waste treatment techniques. To be able to document improvements in sustainability, in each system studied the same set of twenty sustainability indicators were measured. Indicators related to the use of fingerlings, water, diesel oil, electricity, labor, chemicals and antibiotics.

Also, indicators related to nutrient utilization efficiencies and waste discharge were monitored. In addition, a sampling scheme, allowing to calculate organic matter, nitrogen, phosphorous and chemical oxygen demand mass balances covering a full production cycle and applicable in different production systems, was developed. Overall, from a sustainability point of view, striped catfish culture in ponds compared well to other important aquaculture species.

Although favorable, it was concluded that water, chemicals and antibiotics use, survival, and the amounts of waste discharged could be further reduced through recirculation and treatment of solid wastes. The realized improvements through RAS technology and waste treatment technology were quantified in lab or pilot scale experiments. Large improvements were realized for water, antibiotic and chemical use, survival, waste discharge and color grade of striped catfish fillets at harvest. In addition, in RAS, utilization efficiencies of nutrients supplied through feeding were improved.

Solid wastes removed from ponds or RAS could be partially re-used by making compost or producing methane for generating electricity. Another approach tested was the integration of a denitrification reactor in the recirculation system, which allowed to decompose solid waste and reduce nitrogen discharge. Denitrification in RAS did not affect fish growth, nutrient retention efficiencies and the quality of the fish fillets produced, and thus also improved sustainability of striped catfish farming.

In conclusion, application of recirculation and waste treatment techniques tested in this thesis improved the sustainability for striped catfish culture. The challenge remains to scale up RAS and waste treatment technology for striped catfish to the production volumes handled in outdoor ponds without raising production costs.

Economic analysis of technological innovations to improve sustainability of pangasius production in Vietnam
Ngoc, Pham Thi Anh - \ 2016
University. Promotor(en): Alfons Oude Lansink; Johan Verreth, co-promotor(en): Miranda Meuwissen. - Wageningen : Wageningen University - ISBN 9789462579880 - 141
fish production - fishes - innovations - economic analysis - sustainability - fish culture - vietnam - visproductie - vissen - innovaties - economische analyse - duurzaamheid (sustainability) - visteelt

In response to increasing concerns about sustainable production, a growing number of European customers expect seafood products to be certified, for example by the Aquaculture Stewardship Council (ASC) certification. Water purification technologies such as Recirculating Aquaculture Systems (RAS) could be a potential solution to reduce waste discharge and to improve water quality in fish ponds as a response to environmental regulations. In order to provide useful insights to consider investments in RAS, the overall objective of this thesis was to perform an economic analysis of technological innovations such as RAS to improve the sustainability of pangasius production in Vietnam.

This thesis first uses Data Envelopment Analysis to measure input- and output-specific technical and scale inefficiency of pangasius farmers in the traditional system and uses a bootstrap truncated regression to assess the impact of farmers’ demographics and farm characteristics on these technical inefficiencies. Second, the economic feasibility of RAS in pangasius farming is analysed using a capital budgeting approach and stochastic simulation accounting for uncertainty in key parameters. Next, key determinants influencing the adoption of RAS by pangasius farmers are investigated using a choice experiment. Finally, price transmission along the international supply chain of pangasius, from the Vietnamese farm to the Polish retail stage is analysed using a vector autoregressive error correction model framework.

The results show that inadequate management skills in using capital assets and improper methods for producing fish are the main challenges for enhancing the performance of Vietnamese pangasius production. Location of the farm in a saltwater intrusion area is positively associated with inefficiency of producing fish. The results suggest further that when shifting from the traditional system to RAS, the Net Present Value (NPV) of the investment in RAS is expected to substantially increase, for both medium (1-3 ha) and large (equal or greater than 3 ha) farms. Lack of trust in receiving a price premium, inadequate access to finance and uncertainty about the actual performance of RAS systems are constraints for the adoption of RAS. Finally, our study provides evidence that price signals at the Polish-Vietnamese retail stage were transmitted back to wholesale, export and Vietnamese pangasius farms stages.

Monitoring en evaluatie Pilot Zandmotor fase 2 : data rapport Visbemonstering najaar 2015
Hal, R. van; Pennock, I. ; Hoek, R. - \ 2016
IJmuiden : IMARES Wageningen UR (IMARES rapport C059/16) - 27
vissen - benthos - bemonsteren - zee-organismen - zandsuppletie - kustbeheer - natuurontwikkeling - zuid-holland - fishes - sampling - marine organisms - sand suppletion - coastal management - nature development
Dit rapport beschrijft de vis en epibenthos bemonstering op en rond de Zandmotor in het najaar van 2015. De bemonstering is uitgevoerd van 7 t/m 9 oktober en 19 oktober 2015 vanaf het schip de YE42, gebruikmakend van een 3-meter boomkor voorzien van wekkerkettingen en een net met een maaswijdte van 20mm. Met dit tuig zijn in totaal 68 vistrekken uitgevoerd, met een beviste afstand tussende 491 en540 m, verdeeld over een 9-tal raaien, loodrecht op de voormalige kustlijn. De bemonsteringslocaties zijn op waterdieptes tussen 1,7 en 11,6 m op de raaien geplaatst. Van iedere geslaagde trek zijn de vangsten uitgezocht, en de soorten gedetermineerd en gemeten (lengte en gewicht). De gegevens hiervan zijn opgeslagen in de IMARES database en een overzicht hiervan is weergegeven in dit rapport. De beschrijving van de data is aangevuld met een vergelijking met eerdere jaren ter aanvulling op het tussentijdse evaluatierapport geschreven begin 2015.
Sababank: onderzoek 2011 -2016
Bos, O.G. ; Becking, L.E. ; Meesters, H.W.G. - \ 2016
Wageningen Marine Research - 66 p.
mariene ecologie - mariene gebieden - zee-organismen - vissen - koralen - biodiversiteit - caribisch gebied - marine ecology - marine areas - marine organisms - fishes - corals - biodiversity - caribbean
Saba Bank: Research 2011 - 2016
Bos, O.G. ; Becking, L.E. ; Meesters, H.W.G. - \ 2016
Wageningen Marine Research - 66 p.
marine ecology - marine areas - marine organisms - fishes - corals - biodiversity - caribbean - mariene ecologie - mariene gebieden - zee-organismen - vissen - koralen - biodiversiteit - caribisch gebied
PMR Monitoring natuurcompensatie Voordelta : ontwikkeling vis in de Voordelta na instelling bodembeschermingsgebied ter compensatie van de aanleg Tweede Maasvlakte
Tulp, Ingrid ; Tien, Nicola ; Damme, Cindy van - \ 2016
IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C089/16) - 148
vissen - monitoring - natuurcompensatie - natuurbeheer - marien milieu - bodembescherming - fishes - nature compensation - nature management - marine environment - soil conservation
In deze rapportage worden de bevindingen gepresenteerd van de bemonsteringen vanaf de T0 (2005-2007) tot na de instelling van het Bodembeschermingsgebied (2009-nu), voor zover mogelijk tot en met de resultaten van voorjaar 2013.
Microbial interactions in the fish gut
Giatsis, Christos - \ 2016
University. Promotor(en): Johan Verreth, co-promotor(en): Marc Verdegem; Detmer Sipkema. - Wageningen : Wageningen University - ISBN 9789462578777 - 196
fishes - tilapia - larvae - microbial interactions - intestinal microorganisms - intestines - dynamics - fish feeding - probiotics - fish culture - aquaculture - vissen - larven - microbiële interacties - darmmicro-organismen - darmen - dynamica - visvoeding - probiotica - visteelt - aquacultuur

Aquaculture has realized considerable growth over the past years while the world demand on seafood has been increasing. As aquaculture intensifies, the production sector needs to tackle major bottlenecks such as suboptimal growth and high and unpredictable mortality, especially in larval cultures. Fish-microbe interactions are closely related to overall fish health. To obtain a healthy and resilient microbial community (MC), it is important to understand the underlying mechanisms of microbial colonization in the fish gut.

The goal of this thesis was to investigate the role of water and feed microbial communities on shaping gut communities during early development of Nile tilapia.

To determine the contribution of stochasticity to overall variation, we first characterized the spatio-temporal variation in MC composition between individuals reared within the same or in replicate recirculating or active suspension systems (RAS vs. AS). Highly similar MCs developed in the gut when larvae shared the same water and diet. Rearing larvae in replicate production systems resulted in significantly different gut communities indicating that compositional replication of the MCs of an ecosystem is not fully predictable. We found that mainly water MCs, and to a lesser degree feed MCs, were associated with changes in MCs. Thus, we could conclude that steering gut MCs can be possible through water MC management tailored on the specifications of the rearing system in use.

Next, the possibility of early life steering of gut communities via microbial manipulations of feed MCs was explored. We hypothesized that gut microbial composition is strongly shaped by selective pressures in the gut and by the MCs present in the water. Thus similar MCs should develop between treatments regardless of the dietary treatments. Fish larvae were fed either a control feed or the control feed containing MCs derived from aerobic, methanogenic or denitrifying sludge reactors. We found that gut microbiota shared a much higher number of operational taxonomic units (OTUs) with microbiota in sludge-based feeds than with water, resulting in distinct gut MCs between treatments. Our findings suggest that Nile tilapia gut MC has a certain plasticity, which makes it amenable to interventions through proper feed microbial management.

Subsequently, we tested the imprinting effect of early exposure to the probiotic Bacillus subtilis on shaping gut MC composition even after the administration of the probiotic discontinues. For this, we constrained the initial contact with microbes from the environment by producing axenic tilapia larvae, which were then exposed to normal husbandry conditions. Early life probiotic exposure affected gut MC composition during B. subtilis administration but also within the first two weeks after its administration stopped, thus indicating that early exposure to the probiotic strain via the water had a sustained impact on gut MC composition.

Finally, overall conclusions and practical implications of our results for aquaculture production were presented. A meta-analysis was also performed to examine (1) the phylogenetic similarity among gut MCs of the same and different fish species reared in different habitats, fed different diets and at different developmental stages and (2) the factors primarily shaping gut MCs. We showed that the selective pressure responsible in shaping gut MC composition highly depends on the host as gut communities clustered primarily together by host and to a lesser extent reflected differences in habitat and diet. The phylogenetic analysis of gut communities revealed a clear clustering by study thus indicating that manipulation of gut communities is conceivable. Study-to-study variation could be attributed to the methodology used for MC analysis highlighting also the importance of methodological uniformity when comparisons between studies are made.

Overall, this thesis provided fundamental knowledge on MC composition and development in aquaculture rearing systems. Although the insights generated by this thesis are still premature to fully explain, predict or steer MC composition, and though additional studies are needed, we believe that, in the long run, this approach will facilitate the development of safe and effective methods for manipulating gut microbial composition to promote fish health in aquaculture rearing systems.

Food from the Sulawesi Sea, the need for integrated sea use planning
Siahainenia, Audrie J. - \ 2016
University. Promotor(en): Herbert Prins; Johan Verreth, co-promotor(en): Fred de Boer. - Wageningen : Wageningen University - ISBN 9789462578869 - 180
mangroves - mangrove forests - fishes - habitats - marine areas - marine environment - fish stocks - environmental management - ecological disturbance - disturbance - sulawesi - mangrovebossen - vissen - mariene gebieden - marien milieu - visstand - milieubeheer - ecologische verstoring - verstoring - celebes

Mangroves occur in the tropics and subtropics region and an important coastal habitat for the artisanal fisheries along the coast of Indonesia. Around 19% of the total mangrove area in the world is located in Indonesia. Besides providing a barrier against coastal/Delta erosion, mangrove forest plays a significant role as a nursery area for most of the marine communities. Unluckily, 57% of the ±3.2 million ha of the mangroves in Indonesia is currently in degraded, mostly because of human activities (anthropogenic disturbance). The primary sources of anthropogenic disturbances to mangroves are increasing population growth rate and demand for seafood products as an essential protein, especially the wild shrimp, in the world market. These resulted in land-use conversion along estuarine areas not only for settlements and plantations but also for aquaculture ponds. The lack of awareness and understanding of the value and function of mangrove ecosystems contributed to the loss and damage the mangroves area.

Therefore, my research and field experiment aimed to quantify the effects of human disturbance on mangroves associated trophic cascades in Indonesia estuarine areas. The study was performed in the Berau District, East Kalimantan, Indonesia between 2005 and 2010. Data of mangrove extent from 1990 in the Berau Delta was used as base data with low human disturbance. We also interviewed the artisanal fishermen about their catches, origins, and fishing locations, in relation to the total catch per unit effort (CpUE).

The results had shown that the total mangroves area in the Berau Delta decreased by 54% between the 1990 and 2009, which led to fragmentation and alteration in the structural complexity of mangroves. The field experiment conducted at three locations with different levels of human disturbances revealed that the species richness was decreased with increased the level of human interference and the marine community tended to be dominated by only a few species. In the highly disturbed areas, the catch of small-scale fishermen tended to be lower. Furthermore, the result from a spatial statistical model indicated that the disturbance of mangrove habitats was influenced the distribution pattern of shrimp. The total CpUE of small-scale fishery in the study area was relatively small, and the area was probably not overexploited.

As a conclusion, mangroves habitat in the Berau Delta played a significant role in sustaining coastal fisheries. This important ecosystem supports a primary source of marine protein. Mangrove forests can only guarantee these marine resources if the people consciously maintain its viability through a strong management policy.

Vissen in de nieuw aangelegde hoogwatergeul in de Raaijweide bij Venlo
Pollux, B.J.A. ; Korosi, A. ; Nagelkerke, L.A.J. ; Pollux, P.M.J. - \ 2016
Natuurhistorisch Maandblad 105 (2016)5. - ISSN 0028-1107 - p. 100 - 106.
nature development - river forelands - channels - fish fauna - natural areas - limburg - flood control - aquatic ecology - fishes - natuurontwikkeling - uiterwaarden - kanalen, klein - visfauna - natuurgebieden - hoogwaterbeheersing - aquatische ecologie - vissen
De afgelopen decennia is er in toenemende mate aandacht gekomen voor natuurontwikkeling in rivieruiterwaarden. Een belangrijk onderdeel hiervan vormt het graven van hoogwatergeulen: korte nevenlopen die (bij hoogwater) parallel aan de hoofdstroom met de rivier meestromen en die gedurende de rest van het jaar ook water houden. Zulke geulen worden vaak gekenmerkt door een lagere stroomsnelheid dan de rivier zelf, gevarieerde oevers met ondiepe zandbanken en een rijke oever- en onderwatervegetatie. In dit artikel wordt de visfauna beschreven in een recent aangelegde hoogwatergeul in natuurgebied de Raaijweide bij Venlo.
Omvang en overleving van schubvis bijvangst in fuikenvisserij nabij kunstwerken
Griffioen, A.B. ; Keeken, O.A. van; Chen, C. ; Blom, E. ; Schram, E. ; Graaf, M. de; Winter, Hendrik V. - \ 2016
IMARES (Rapport / IMARES C140/15) - 53 p.
visserij - bijvangst - vissen - schade - dierenwelzijn - mortaliteit - fisheries - bycatch - fishes - damage - animal welfare - mortality
Deze rapportage geeft een schatting van de omvang van de bijvangst in de beroepsvisserij nabij kunstwerken op basis van fuikvangsten en diverse interviews. Daarnaast is er een experiment uitgevoerd waarbij er gekeken is naar de overleving van schubvis nadat zij in fuiken hebben gezeten. Hierbij zijn de baars en blankvoorn gebruikt om de overleving te testen in relatie tot de volgende variabelen: aanwezigheid aal: geen (0 stuks), weinig aal (7 stuks) en veel aal (50 stuks), staduur van de fuik: 3, 6 of 9 dagen en dichtheid van vis in een fuik: 60 stuks tegenover 240 stuks.
Vangst- en inspanningsadviezen over snoekbaars, baars, blankvoorn en brasem in het IJssel-/Markermeer: visseizoen 2016/2017
Tien, N.S.H. ; Hammen, T. van der - \ 2016
IMARES (Rapport / IMARES C019/16) - 75 p.
visstand - vissen - aquatische ecologie - visserijbeleid - natuurbeheer - ijsselmeer - visvangsten - fish stocks - fishes - aquatic ecology - fishery policy - nature management - lake ijssel - fish catches
Het Ministerie van Economische Zaken (EZ) wil komen tot wetenschappelijk onderbouwd duurzaam beheer van snoekbaars, baars, blankvoorn en brasem in het IJsselmeer en Markermeer. Voor alle vier bestanden is de beleidsdoelstelling voor visseizoen 2016/2017 geformuleerd als “een zekere mate van herstel”. Voor het behalen van deze beleidsdoelstelling zijn inspanningsadviezen gevraagd over de staandwantvisserij en de zegenvisserij, gecombineerd voor het IJsselmeer en Markermeer. Dit rapport bevat een primair en, op verzoek van de opdrachtgever, een alternatief advies. Het primaire advies is beschreven in hoofdstuk 1, het alternatieve advies is uitgewerkt in hoofdstukken 2 tot en met 8. Deze adviezen hebben als doelstelling het voorkomen van verdere achtergang van de visbestanden. Voor de doelstelling ‘een zekere mate van herstel’ worden aanvullende adviezen gegeven. Alle drie adviezen zijn samengebracht in hoofdstuk 9.
Achtergronddocument Rode Lijst Vissen 2011 : zoutwatervissen; analyse en documentatie in 2011 - 2013 publicatie in 2016
Tien, N.S.H. ; Heessen, H.J.L. ; Kranenbarg, Jan ; Trapman, B.K. - \ 2016
IJmuiden : IMARES (Rapport / IMARES C021/16) - 85 p.
vissen - bemonsteren - zout water - bedreigde soorten - zeevissen - fishes - sampling - saline water - endangered species - marine fishes
In 2011-2013 heeft IMARES als onderaannemer van RAVON, in opdracht van het toenmalige Ministerie van Economie, Landbouw en Innovatie (het hedendaagse Ministerie van Economische Zaken), meegewerkt aan het uitvoeren van analyses om tot een voorstel te komen voor een nieuwe Rode Lijst Vissen. Deze analyses zijn uitgevoerd op basis van een door de Nederlandse overheid vastgestelde methodiek om de mate waarin soorten bedreigd zijn vast te stellen. Hierbij zijn door IMARES 59 zoutwatervissoorten onderzocht die gevangen worden in de wetenschappelijke bemonsteringsprogramma’s IBTS, BTS en DFS. De wetenschappelijke bemonsteringsprogramma’s van IMARES zijn programma’s waarin jaarlijks volgens een vaste methode met boomkortuigen wordt gevist om gegevens te verzamelen over de toestand van Noordzeevisbestanden. Het voorliggende rapport bevat de beschrijving en uitkomst van de analyses zoals uitgevoerd in 2011 en 2012 door IMARES. De tekst is grotendeels in 2011-2013 geschreven, door IMARES en RAVON. Op basis van deze analyses, en de analyses van RAVON (zoetwatersoorten) en stichting ANEMOON en Ecosub (zoutwatersoorten) is een nieuwe Rode Lijst Vissen opgesteld welke sinds 2016 van kracht is.
Towards monitoring zoöplankton and small pelagic fish in the Wadden Sea
Couperus, A.S. ; Jak, R.G. ; Flores, H. ; Gastauer, S. ; Fassler, S.M.M. - \ 2016
IJmuiden : IMARES (Report / IMARES C094/13) - 56 p.
zooplankton - fishes - monitoring - acoustics - wadden sea - aquatic ecology - netherlands - zoöplankton - vissen - geluidsleer - waddenzee - aquatische ecologie - nederland
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