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The influence of innovative management alternatives (participatory governance, effort management, decision rules) on biological robustness (BR) in various fisheries relevant to the EU (Baltic, Western Shelf, Faroe Islands, North Sea), was investigated with a numerical simulation model developed in the EU projects EFIMAS (2004–2008) and COMMIT (2004.....

A primary consideration in the evaluation of chemicals is the potential for substances to be absorbed and retained in an organism's tissues (i.e., bioaccumulated) at concentrations sufficient to pose health concerns. Substances that exhibit properties that enable biomagnification in the food chain (i.e., amplification of tissue concentrations at su.....

Viskweek in Nederland vindt vrijwel exclusief plaats in recirculatiesystemen. Naast een laag water- en energieverbruik en controle over de kweekomstandigheden, geeft het recirculatiesysteem een hoge mate van controle over de reststromen van het kweekproces. Al met al biedt het recirculatiesysteem veel aanknopingspunten voor duurzame aquacultuur

Juvenile turbot (Scophthalmus maximus) were exposed periodically and chronically to different levels of un-ionised ammonia (UIA-N) and the subsequent effect on growth and food conversion efficiency was studied. Fish with a mean (SD) initial weight 19.3 (3.9) g, were exposed to five treatments consisting of a control group, two groups (ChronicLow an.....

The impact of a bottom trawl fishery on fish or benthos is often determined by multiplying the frequency of the passing of the trawl by a factor for the effect (i.e., % mortality) of the singular passing of the gear. As fishing intensity in an area is not homogeneously distributed, it is necessary to determine the proportions of the area that are f.....

Probabilistic maturation reaction norms (PMRNs) with up to three explanatory dimensions were estimated for female North Sea plaice. The three-dimensional PMRNs reported here (1) are the first ones to be obtained for any organism, (2) reveal the differential capacity of alternative life-history state variables to predict the onset of reproduction, (.....

Microbiological and sensory changes of maatjes herring stored in air (experiment I) and under modified atmosphere (MAP) (experiments II and III) were evaluated during storage at 4 and 10 °C. Microbial (total and psychrotrophic viable bacteria, lactic acid bacteria and Enterobacteriaceae) counts and chemical analyses (chloride content, fat content, .....

A year-class curve is a plot of log cpue (catch per unit effort) over age for a single year class of a species (in contrast to the better known catch curve, fitted to multiple year classes at one time). When linear, the intercept and slope estimate the log cpue at age 0 and the average rate of total mortality, Z, respectively. Here, we suggest meth.....

Many flatfish species are caught in mixed demersal trawl fisheries and managed by Total Allowable Catch (TAC). Despite decades of fisheries management, several major stocks are severely depleted. Using the Common Fisheries Policy (CFP) as an example, the failure of mixed-fisheries management is analysed by focussing on: the management system; the r.....

Passive sampling of dissolved pollutants in water has been gaining acceptance for environmental monitoring. Previously, an integrative passive sampler consisting of a C18 Empore® disk receiving phase saturated with n-octanol and fitted with low density polyethylene membrane, was developed and calibrated for the measurement of time weighted average .....

In this study, polysaccharide-producing bacteria were isolated from slimes collected from two Finnish and one Spanish paper mill and the exopolysaccharides (EPSs) produced by 18 isolates were characterised. Most of the isolates, selected on the bases of slimy colony morphology, were members of the family Enterobacteriaceae most frequently belonging.....

Annual discard ogives were estimated using generalized additive models (GAMs) for four demersal fish species: whiting, haddock, megrim, and plaice. The analysis was based on data collected on board commercial vessels and at Irish fishing ports from 1995 to 2003. For all species the most important factors influencing annual discard ogives were fleet.....

The aim of this study was to extract collagen from fish skins and investigate the physical properties of the biodegradable films formed from the extracted fish collagen. Extraction of collagen using hydrogen peroxide or enzymatic methods proved to be unsuccessful. A white collagen substance was successfully extracted using a hydrochloric acid extra.....

The phylogeography of thornback rays (Raja clavata) was assessed from European waters, using five nuclear microsatellite loci and mitochondrial cytochome b sequences. Strong regional differentiation was found between the Mediterranean basin, the Azores and the European continental shelf. Allelic and haplotype diversities were high in Portuguese pop.....

European eel, Anguilla anguilla L., has a wide distribution from polar to arid climates. The growth and sex in eels from the River Asi, which is in the most arid region of the species distribution, and at a temperature of 21-27 ºC close to the experimentally determined optimum for the eel were examined. A total of 315 European eels were collected b.....

The scope of this paper is to quantify, for a wide selection of European fisheries, fishing tactics and strategies and to evaluate the benefits of adjusting the definition of. fishing effort using these elements. Fishing tactics and strategies were identified by metiers choices and a series of indices. These indices have been derived to reflect shi.....

Variations in standard length (LS), gape size (SG) and jaw length (LJ) were studied in larval and juvenile gadoids (cod Gadus morhua, haddock Melanogrammus aeglefinus and whiting Merlangius merlangus) from 4 to 70 mm. The increase in SG and LJ was not linear with respect to LS. The relationship was best described by segmented regression lines in al.....

To measure and predict the response of fish communities to exploitation, it is necessary to understand how the direct and indirect effects of fishing interact. Because fishing and predation are size-selective processes, the potential response can be explored with size-based models. We use a simulation approach to describe the relationship between s.....

This report describes the derivation of parameter estimates for the model DYNAMIG for an arctic breeding shorebird, the Knot. DYNAMIG predicts the optimal spring migration of birds, like shorebirds and geese, that depend of a chain of discrete sites, to travel between their breeding grounds and their wintering grounds. An important parameter is the.....

In dit rapport wordt een overzicht gegeven van de biologische variabelen in gebieden waar door de gaswinning van de velden Nes, Moddergat, Lauwersoog-C, Lauwersoog-West, Lauwersoog-Oost en Vierhuizen bodemdaling verwacht wordt. De focus is vooral op de buitendijkse vastelandkwelders en de kombergingsgebieden het Pinkegat en de Zoutkamperlaag. Alter.....

Sinds 1990 is het aantal Scholeksters dat in Nederland broedt met 50% afgenomen. Een vergelijkbare afname van meer dan 40% heeft zich voorgedaan in het Waddengebied. Dit rapport beschrijft de resultaten van intensief bestudeerde en eveneens sterk afgenomen broedpopulaties van de Scholekster Haematopus ostralegus op Schiermonnikoog en Texel. Vanaf 1.....

Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made by an energetic model of larval requirements. Bivalve larvae wer.....

Dover sole were reared at 6 different stocking densities between 0.56 and 12.6 kg/m2 with duplicate tanks for each treatment. The experiment lasted for 55 days. Water quality effects on growth were minimised by making the flow rate per tank proportional to the feeding load. Individual initial and final weights were determined for all fishes to calc.....

Background Triggered by the requirement of Water Framework Directive for a good ecological status for European river systems till 2015 and by still existing lacks in tools for cause identification of insufficient ecological status MODELKEY (http://www.modelkey.org), an Integrated Project with 26 partners from 14 European countries, was started in.....

Den Helder Airport verwacht in de komende jaren een toename van de vraag naar vliegbewegingen van civiele helikopters naar offshore-installaties op de Noordzee. Een groot deel van deze extra vliegbewegingen zal plaatsvinden boven het Balgzand, dat deel uitmaakt van de Speciale Beschermingszone Waddenzee. Overschrijding van het nu beschikbare maxima.....

Comprehensive two-dimensional gas chromatography (GCxGC) coupled with micro electron-capture and time-of-flight mass spectrometric (TOF-MS) detection has been used to analyse technical toxaphene. An HP-1xHT-8 column combination yielded highly structured chromatograms and revealed a complex mixture of over 1000 compounds what is significantly higher.....

Fish oils extracted from marinated herring (frozen and unfrozen) byproducts and maatjes herring byproducts were evaluated on their chemical and sensory properties. The obtained crude oils had very low content of copper (<0.1 mg/kg oil), and iron values were 0.8, 0.1, and 0.03 mg/kg oil, respectively, for oil from maatjes and frozen and fresh byprod.....