- Eveline Diopere (1)
- Gregory E. Maes (1)
- Atle Foss (1)
- K. Frankena (1)
- Sara G. Vandamme (1)
- D.M. Gillis (1)
- T. Gray (1)
- R. Hal van (1)
- J.G. Hiddink (1)
- Jeroen Houdt van (1)
- T. Hutton (1)
- Pascal I. Habluetzel (1)
- O.A. Keeken van (1)
- Albert Kjartan Dagbjartarson Imsland (1)
- Bert Lambooij (1)
- J.L. Leeuwen van (1)
- W. Ouweltjes (1)
- G.J. Piet (2)
- J.J. Poos (2)
- A.D. Rijnsdorp (4)
- Bjørn Roth (1)
- K. Smits (1)
- Fausto Tinti (1)
- C. Ulrich (1)
- Y. Vermard (1)
- Hans Vis van de (1)
- J.T.N. Werf van der (1)
Physiological response of temperature shocks in turbot and sole
Foss, Atle ; Imsland, Albert Kjartan Dagbjartarson ; Vis, Hans van de; Abbink, Wout ; Lambooij, Bert ; Roth, Bjørn - \ 2019
Journal of Applied Aquaculture 31 (2019). - ISSN 1045-4438 - p. 34 - 47.
Hypothermia - live chilling - sole - temperature - turbot
In the present study, selected temperature drops were examined to investigate the effects of live chilling on stress and welfare in turbot and sole. This study demonstrated that rapid temperature drops from 11°C–12°C and 18°C–18.7°C to 4°C–0°C in turbot resulted in higher blood sodium and potassium at 0°C (164 mmol l−1, 4.4 mmol −1) compared to 4°C (153 mmol l−1, 3.1 mmol −1), indicating osmoregulatory disturbance. A rapid temperature drop from 18°C to 0°C in Senegal sole also resulted in higher blood sodium and potassium at 0°C (164 mmol l−1, 4.8 mmol −1) compared to the control group at 18°C (157 mmol l−1, 3.2 mmol −1). Based on present findings, we conclude that immersion in ice water will have a negative effect on the animal osmoregulatory capacity, and we recommend that turbot and sole are stunned before slaughter.
Seascape genetics of a flatfish reveals local selection under high levels of gene flow
Diopere, Eveline ; Vandamme, Sara G. ; Habluetzel, Pascal I. ; Cariani, Alessia ; Houdt, Jeroen van; Rijnsdorp, A.D. ; Tinti, Fausto ; Volckaert, Filip A.M. ; Maes, Gregory E. - \ 2018
ICES Journal of Marine Science 75 (2018)2. - ISSN 1054-3139 - p. 675 - 689.
fish - isolation by distance - local adaptation - Northeast Atlantic Ocean - outlier locus - population genomics - SNP - sole
Local adaptation is often found to be in a delicate balance with gene flow in marine species with high dispersal potential. Genotyping with mapped transcriptome-derived markers and advanced seascape statistical analyses are proven tools to uncover the genomic basis of biologically relevant traits under environmental selection. Using a panel of 426 gene-linked single nucleotide polymorphisms (SNPs), we scanned 17 samples (n¼539) of sole (Solea solea L.) from the Northeast Atlantic Ocean and applied a node-based seascape analysis. Neutral loci confirmed a clear distinction between the North Sea–Baltic Sea transition zone and the other Eastern Atlantic samples. At a more subtle level,
the latter unit split in an English Channel and North Sea group, and a Bay of Biscay and Atlantic Iberian coast group. A fourth group, the Irish and Celtic Sea, was identified with 19 outlier loci. A pattern of isolation by distance (IBD) characterized the latitudinal distribution. Seascape analyses identified winter seawater temperature, food availability and coastal currents to explain a significant component of geographically distributed genetic variation, suggesting that these factors act as drivers of local adaptation. The evidence for local adaptation is in line with the current understanding on the impact of two key ecological factors, the life-history trait winter mortality and the behaviour of inshore/offshore spawning. We conclude that the subtle differentiation between two metapopulations (North Sea and Bay of Biscay) mirrors local adaptation.
At least three genomic regions with strong population differentiation point to locally divergent selection. Further functional characterization of these genomic regions should help with formulating adaptive management policies.
Effects of flooring and restricted freestall access on behavior and claw health of dairy heifers
Ouweltjes, W. ; Werf, J.T.N. van der; Frankena, K. ; Leeuwen, J.L. van - \ 2011
Journal of Dairy Science 94 (2011)2. - ISSN 0022-0302 - p. 705 - 715.
free stalls - cattle - cows - lesions - lactation - lameness - sole - hemorrhages - prevalence - locomotion
Claw health, locomotion, feed intake, milk yield, body weight, activity, and lying and standing behavior of dairy heifers were monitored in a single dairy herd during the first 3 mo after calving. During the first 8 wk after calving, 2 treatments were applied: restricted freestall access by closing the stalls between 2300h and 0500h (yes or no) and alley flooring (concrete or rubber topped slatted floors). Apart from treatments, housing was identical. The animals were kept in small groups (n=4 to 6) in adjacent barn pens. Thereafter, the animals were kept in 1 group in a freestall section with concrete slatted floor and unrestricted access to the stalls for 5 wk. All animals were fed the same partial mixed ration. We hypothesized that (1) hard flooring causes high mechanical load of the claws and (2) restricted freestall access causes prolonged standing bouts and reinforced effects of hard flooring on claws. The heifers had only minor claw lesions before first calving, and the prevalence and severity of sole hemorrhages increased during the first 3 mo after calving (from 0.24±0.08 to 1.18±0.14 and from 0.04±0.01 to 0.24±0.02, respectively), particularly in the outer hind claws. Animals kept on rubber alley flooring had lower average hemorrhage scores in wk 9 (0.13±0.03 vs. 0.21±0.03) and wk 14 (0.20±0.03 vs. 0.27±0.03) after calving, had a slower feed intake (3.05±0.14 vs. 3.46±0.14 g/s) and spent more time feeding (7.3±0.3 vs. 6.6±0.3 min/h) than animals kept on hard concrete alley floors. Restricted freestall access resulted in fewer standing bouts per day (14.4±1.0 vs. 17.9±1.0) and more strides per hour (99.8±5.4 vs. 87.2±5.4) without changing overall standing time (15.0±0.3 vs. 14.7±0.3 h/d) and did not affect the occurrence of sole hemorrhages. The animals with no overnight freestall access spent more time standing (55.9±0.9 vs. 35.8±0.9 min/h) and feeding (7.8±0.3 vs. 4.3±0.3 min/h) between 2300 and 0500h and less during the rest of the 24-h period (31.3±0.8 vs. 37.0±0.8 min/h and 6.8±0.3 vs. 7.6±0.3 min/h). Thus, the animals adapted to restricted freestall access, that caused increased overnight standing, by additional lying down during the day and used part of the extra standing time at night for feeding. The restrictions probably had only a minor effect on the mechanical load of their claws. Therefore, the first part of the hypothesis was confirmed and the second part was rejected
Challenges in integrating shrot-term behaviour in a mixed-fishery Management Strategies Evaluation frame: a case study of the North Sea flatfish fishery
Andersen, B.S. ; Vermard, Y. ; Ulrich, C. ; Hutton, T. ; Poos, J.J. - \ 2010
Fisheries Research 102 (2010)1-2. - ISSN 0165-7836 - p. 26 - 40.
fishing location choice - fleet dynamics - simulation-models - commercial catch - trip choice - tactics - plaice - rates - sole
This study presents a fleet-based bioeconomic simulation model to the international mixed flatfish fishery in the North Sea. The model uses a Management Strategies Evaluation framework including a discrete choice model accounting for short-term temporal changes in effort allocation across fisheries. A simplified random utility model was used based on the expected revenue (or economic attractiveness) and two tradition parameters related to short and long term historical fishing patterns. All three parameters were significant. Even though reactions and adaptations vary between fleets, the estimated conservative behaviour of the main fleets led to only marginal effect at the stock level. The importance of accounting for fleet behaviour was then evaluated using an elasticity analysis to explore how increased weight of economic attractiveness contributes to changes in the biological output and positive increase in the economic performance of the individual fleets. This showed the existence of a window of sensitivity of the model to the behaviour assumptions. The study highlights the challenge of implementing an effort allocation model in a general framework of Management Strategies Evaluation for mixed-fisheries, and illustrates the necessary trade-offs between very detailed numerical relationships and the representation of aggregated processes.
How climate warming impacts the distribution and abundance of two small flatfish species in the North Sea
Hal, R. van; Smits, K. ; Rijnsdorp, A.D. - \ 2010
Journal of Sea Research 64 (2010)1-2. - ISSN 1385-1101 - p. 76 - 84.
vissen - populatiedichtheid - vismigratie - klimaatverandering - noordzee - fishes - population density - fish migration - climatic change - north sea - arnoglossus-laterna walbaum - solenette buglossidium-luteum - long-term trends - marine fishes - west-coast - plaice - scaldfish - growth - sole - assemblage
Climate change, specifically temperature, affects the distribution and densities of species in marine and terrestrial ecosystems. Here, we looked at the effect of temperature during winter and spawning period on latitudinal range shifts and changes in abundance of two non-commercial North Sea fish species, solenette (Buglossidium luteum) and scaldfish (Arnoglossus laterna). Both species have increased in abundance and moved to the north since the late 1980s, coinciding with a series of mild winters. In 1996, following a very cold winter, the abundance of both species temporarily decreased as they retracted to the south. The shift in temperature affected adult habitat conditions, allowing them to immigrate into new areas where they subsequently reproduced successfully. We can conclude this because recruitment improved following the increase in abundance. The recruitment relates significantly to the higher adult stock and higher temperatures. The predictions of higher average temperatures and milder winters in the North Sea make it likely that these species will increase further in abundance and move northward. The observed increase in abundance of these small flatfish species will affect the North Sea food web and therefore commercial species, e.g. plaice, by predation on juveniles and competition for benthic food resources
The discard problem - A comparative analysis of two fisheries: The English Nephrops fishery and the Dutch beam trawl fishery
Catchpole, T. ; Keeken, O.A. van; Gray, T. ; Piet, G.J. - \ 2008
Ocean & Coastal Management 51 (2008)11. - ISSN 0964-5691 - p. 772 - 778.
north-sea plaice - catch - sole
Discarding is the throwing overboard of unwanted fish or benthic animals [In this study, we define discards in terms of discarded edible fish, crustaceans and benthic organisms. We exclude, therefore, discards of plant material, offal, sea mammals and sea birds.] that have been caught by sea fishing vessels. Some estimates suggest that up to 25% of the global amount of fish caught is discarded annually. In this comparative analysis of discarding in two contrasting North Sea fisheries ¿ the English Nephrops fishery and the Dutch beam trawl fishery ¿ we discuss the effectiveness of measures that might reduce their rates of discarding, including management measures, market forces and fisher's behaviour. Our findings are that despite the many differences between the two fisheries and their respective discard problems, one common thread ¿ the importance of appropriate incentives ¿ runs through both of them.
Can bottom trawling disturbance increase food production for a commercial fish species?
Hiddink, J.G. ; Rijnsdorp, A.D. ; Piet, G.J. - \ 2008
Canadian Journal of Fisheries and Aquatic Sciences 65 (2008)7. - ISSN 0706-652X - p. 1393 - 1401.
plaice pleuronectes-platessa - north-sea plaice - marine reserves - impacts - communities - habitats - density - growth - sole - area
Fishery closures and marine protected areas are increasingly being used as tools to achieve sustainable fisheries. The ¿plaice box¿, a gear restriction area in the North Sea that was established to reduce the bycatch of undersized plaice (Pleuronectes platessa), is considered ineffective because there has been a shift in the distribution of juvenile plaice to the waters that remained open to bottom trawlers. Here we examine the hypothesis that bottom trawling benefits the small benthic invertebrates that form the food source for plaice and that the plaice box had a negative impact on food production for plaice. A size-based model of benthic communities indicates that the production of prey was low without trawling and maximal in areas that are trawled once to twice a year. Therefore, bottom disturbance may improve the feeding conditions for species that feed on small invertebrates. As plaice aggregate at the locations with the highest benthic biomass, this may explain the observed redistribution to areas outside the plaice box. We conclude that the plaice box may not have been the most appropriate measure to protect plaice from discarding and that the species¿ ecology should be considered when choosing the most appropriate management measure to achieve an objective.
Behavioral inferences from the statistical distribution of commercial catch: patterns of targeting in the landings of the Dutch beam trawler fleet
Gillis, D.M. ; Rijnsdorp, A.D. ; Poos, J.J. - \ 2008
Canadian Journal of Fisheries and Aquatic Sciences 65 (2008)1. - ISSN 0706-652X - p. 27 - 37.
effective fishing effort - north-sea - competitive interactions - abundance - fisheries - dynamics - plaice - model - sole - estimators
The objective identification of targeting behavior in multispecies fisheries is critical to the development and evaluation of management measures. Here, we illustrate how the statistical distribution of commercial catches can provide information on species preference that is consistent with economic data but not a simple function of price. Using the Dutch beam trawl fishery from 1998 to 2003, we show that the distribution of the log10-transformed catch rates of preferred species exhibit greater negative skews than less preferred species. Furthermore, subsets of the fleet employing spatially distinct strategies generate the expected patterns in the skews of their catch distributions. A simple model is presented to illustrate a behavioral mechanism for variation in skews and identify circumstances where it could apply. As a result of this analysis we propose that (i) catch distributions should be examined by species when investigating targeting behavior and (ii) changes in error structure over time can be expected in comparisons of catch statistics such as those used to create abundance indices or estimate fishing power.