References of "Bouquegneau, Jean-Marie"
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See detailNitrogen dynamics in Posidonia oceanica cuttings: implications for transplantation experiments
Lepoint, Gilles ULg; Vangeluwe, Denis; Eisinger, Michael et al

in Marine Pollution Bulletin (2004), 48(5-6), 465-470

A N-15 tracer study was performed during an experimental transplantation trial of natural Posidonia oceanica cuttings. The experiment was done in situ at 17 m depth in the Revellata Bay (Calvi, NW Corsica ... [more ▼]

A N-15 tracer study was performed during an experimental transplantation trial of natural Posidonia oceanica cuttings. The experiment was done in situ at 17 m depth in the Revellata Bay (Calvi, NW Corsica, France). Despite high survival rates of transplants (>90%) after one year, the weight and the N content of transplants are significantly lower than those of reference plants. In absence of roots, the transplants are not able to meet their N requirement because, leaf uptake is insufficient to replenish the N lost during the natural leaf decay. This could constitute a major cause of long-term failure for transplantation experiments or natural recolonisation processes. The increase of the N-15 content in the roots shows that the plant re-allocates the nitrogen of one organ (i.e. leaves, rhizomes) to ensure the growth of another (i.e. roots). (C) 2003 Elsevier Ltd. All rights reserved. [less ▲]

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See detailTrace metal and stable isotope measurements (delta C-13 and delta N-15) in the harbour porpoise Phocoena phocoena relicta from the Black Sea
Das, Krishna ULg; Holsbeek, Ludo; Browning, Julie et al

in Environmental Pollution (2004), 131(2),

Stable carbon and nitrogen isotopes (delta(13)C and delta(15)N) and trace metals (Cd, Zn, Cu, Fe, Se, and Hg) were analysed in the tissues of 46 harbour porpoises (Phocoena phocoena relicta) caught in ... [more ▼]

Stable carbon and nitrogen isotopes (delta(13)C and delta(15)N) and trace metals (Cd, Zn, Cu, Fe, Se, and Hg) were analysed in the tissues of 46 harbour porpoises (Phocoena phocoena relicta) caught in fishing nets along the Ukrainian coasts between 1997 and 1998. Mean delta(13)C values differed significantly between male and female harbour porpoises suggesting a trophic segregation between sexes with a more coastal distribution for females at least during their gestation and nursing periods. Hepatic Hg was correlated to delta(13)C measurements, reflecting a different exposure linked to coastal vs offshore feeding habitats. A geographical comparison with existing data from other regions showed general low levels of Hg, Cd, Cu and Zn in the tissues of harbour porpoises from the Black Sea compared to other Atlantic and North Sea areas. (C) 2004 Elsevier Ltd. All rights reserved. [less ▲]

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See detailEcological and pathological factors related to trace metal concentrations in harbour porpoises Phocoena phocoena from the North Sea and adjacent areas
Das, Krishna ULg; Siebert, Ursula; Fontaine, Michaël ULg et al

in Marine Ecology. Progress Series (2004), 281

There is growing concern about the health status of the harbour porpoise Phocoena phocoena in the North Sea and adjacent areas. The interaction between toxicological results (Zn, Cd, Cu, Fe, Se, Hg ... [more ▼]

There is growing concern about the health status of the harbour porpoise Phocoena phocoena in the North Sea and adjacent areas. The interaction between toxicological results (Zn, Cd, Cu, Fe, Se, Hg), stable isotope data (delta(13)C and delta(15)N) and the most common pathological findings, namely emaciation and lesions of the respiratory system, were investigated in 132 porpoises collected along the coasts of northern France, Belgium, Germany, Denmark, Iceland and Norway between 1994 and 2001. The body condition of harbour porpoises stranded on the French, Belgian and German coasts was poor compared to that of by-catch individuals from Iceland and Norway, as reflected by blubber thickness and hepatic to total body-mass ratio. High Zn and Hg concentrations were observed in some porpoises collected along the southern North Sea coast compared to by-catch individuals from Iceland, Norway and the Baltic Sea. Increasing Zn levels were observed with deteriorating health condition (emaciation and bronchopneumonia), while Hg increases were not significant. The increases were not related to shrinking liver mass which remained unchanged. These observations indicate a general redistribution of trace metals within the organs (muscles and blubber to liver), as a result of protein and lipid catabolism. Muscle delta(13)C and delta(15)N values remained unchanged with deteriorating body condition. Cd concentrations were associated only with age and low delta(15)N values, indicating that high Cd concentrations in Iceland and Norway porpoises may be partly diet-related, i.e. a result of Cd contaminated prey. [less ▲]

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See detailNorth Sea seabirds and marine mammals: pathology and ecotoxicology
Debacker, Virginie ULg; Coignoul, Freddy ULg; Das, Krishna ULg et al

Report (2004)

Les Bancs de Flandres accueillent, en hiver, une importante population d'oiseaux pélagiques. Dans le passé, ils étaient également largement fréquentés par les mammifères marins. De nos jours, on ne les ... [more ▼]

Les Bancs de Flandres accueillent, en hiver, une importante population d'oiseaux pélagiques. Dans le passé, ils étaient également largement fréquentés par les mammifères marins. De nos jours, on ne les observe que très rarement et, chaque année, quelques-uns d'entre eux et des centaines d'oiseaux sont trouvés échoués le long de la côte flamande. Ces espèces doivent être protégées, et le but de ce projet de recherche est d'étudier l'état de santé de leurs populations, son évolution temporelle, les pathologies observées et les contaminants associés, ainsi que les causes possibles de mortalités inhabituelles. La nuisance d'origine humaine la plus importante pour les oiseaux marins semble être la pollution par les hydrocarbures, mais les causes effectives des échouages des oiseaux qui ne sont pas mazoutés, et de la rareté des mammifères, restent inconnues (autres pollutions chimiques, diminution de la nourriture disponible, maladies... ?). [less ▲]

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See detailPerfluorochemicals in harbour porpoises
Van de Vijver, K. I.; Hoff, P. T.; Das, Krishna ULg et al

Poster (2004)

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See detailPerfluorinated chemicals infiltrate ocean waters: Link between exposure levels and stable isotope ratios in marine mammals
Van de Vijver, Kristin Inneke; Hoff, Philippe Tony; Das, Krishna ULg et al

in Environmental Science & Technology (2003), 37(24), 5545-5550

This is the first study to report on concentrations of perfluorinated organochemicals (FOCs) in marine mammals stranded along the southern North Sea coast in relation to stable nitrogen and carbon isotope ... [more ▼]

This is the first study to report on concentrations of perfluorinated organochemicals (FOCs) in marine mammals stranded along the southern North Sea coast in relation to stable nitrogen and carbon isotope ratios (delta(15)N and delta(13)C). The presence of FOCs in top predators such as marine mammals would indicate a potential biomagnification of these compounds and their widespread occurrence. Liver and kidney tissues of nine marine mammal species have been sampled. Among all the measured FOCs compounds, PFOS (perfluorooctane sulfonate) was predominant in terms of concentration. The highest PFOS concentrations were found in the liver of harbor seal compared to white-beaked dolphin, harbor porpoise, gray seal, sperm whale, white-sided dolphin, striped dolphin, fin whale, and hooded seal. PFOS concentrations differed significantly between sexes and age classes in harbor porpoises. Stable isotope measurements (delta(13)C and delta(15)N) were used in this study to describe the behavior of contaminants in food webs. We found a significant (p < 0.05) linear relationship between PFOS concentrations in livers of harbor porpoises and both Muscle delta(13)C and delta(15)N measurements. Harbor and gray seals and white-beaked dolphin, which displayed the highest trophic position, contained the highest PFOS levels, while offshore feeders such as sperm whales,fin whales, striped dolphin, and white-sided dolphin showed lower PFOS concentrations than inshore species. [less ▲]

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See detailLevels and enantiomeric signatures of methyl sulfonyl PCB and DDE metabolites in livers of harbor porpoises (Phocoena phocoena) from the southern North Sea
Chu, Shaogang; Covaci, Adrian; Haraguchi, Koichi et al

in Environmental Science & Technology (2003), 37(20), 4573-4578

The concentration of 26 methyl sulfonyl metabolites of polychlorinated biphenyls (MeSO2-PCBs) and of p,p'-DDE (MeSO2-DDE) were determined in 19 liver samples from harbor porpoises (Phocoena phocoena ... [more ▼]

The concentration of 26 methyl sulfonyl metabolites of polychlorinated biphenyls (MeSO2-PCBs) and of p,p'-DDE (MeSO2-DDE) were determined in 19 liver samples from harbor porpoises (Phocoena phocoena) stranded between 1997 and 2000 on the Belgian and French North Sea Coasts. The total concentration of MeSO2-PCBs ranged from 39 to 4221 ng/g lipid weight (lw) and were generally higher in adults (age >2 yr, range 969-4221 ng/g lw) than in juveniles (age <2 yr, range 39-1815 ng/g lw). The concentrations of MeSO2-DDE were generally also higher in adults (2196 ng/g lw) than in juveniles (0.5-60 ng/g lw). Congeners 3- and 4-MeSO2-CB101 were the dominating metabolites in all samples. Due to their preferential retention in the liver, the MeSO2-PCB congeners could be divided into two groups. The first group was dominated by the 3-MeSO2-PCB congeners and consisted of MeSO2-CB31, -CB49, -CB52, -CB87, and -CB101, which all have a 2,5-chlorine substitution in the phenyl ring containing the methyl sulfonyl group. The second group was dominated by the 4-MeSO2-PCB congeners and consisted of MeSO2-CB64, -CB91, -CB110, and -CB132, which all have a 2,3,6-chlorine substitution. The ratios of sum of PCBs/sum of MeSO2-PCBs and p,p-DDE/MeSO2-DDE differed greatly between individual subjects and ranged from 15 to 419 and from 17 to 1088, respectively. The ratio between the precursor PCB congeners and their corresponding metabolites ranged from 0.6 (CB49) to 175 (CB174). Enantiomeric fractions (EFs) for MeSO2-PCB atropisomers, which include 3-MeSO2-CB132, 3-MeSO2-CB149, 4-MeSO2-CB149, 3-MeSO2-CB174, and 4-MeSO2-CB174, were also measured in 8 out of the 19 subjects. High enantiomeric excess (EF > 0.73 or EF < 0.23) for the measured chiral MeSO2-PCB congeners was found in all samples. This result may suggest that one atropisomer may be preferentially formed in harbor porpoises or that the atropisomers are retained in a highly selective manner. [less ▲]

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See detailRapport sur la numérisation et l’avenir des bibliothèques de l’Université de Liège
Bouquegneau, Jean-Marie ULg; Denooz, Joseph ULg; Gathon, Henry-Jean ULg et al

Report (2003)

Les missions confiées par le Recteur de l'Université de Liège au groupe de travail chargé de rédiger ce rapport étaient : • Organiser le mieux et le plus rapidement possible le développement du ... [more ▼]

Les missions confiées par le Recteur de l'Université de Liège au groupe de travail chargé de rédiger ce rapport étaient : • Organiser le mieux et le plus rapidement possible le développement du numérique dans les bibliothèques ; • Apporter des solutions aux problèmes d’essaimage des budgets et des ressources humaines. Pour répondre à ces objectifs, le Groupe de travail a commencé par relever les principaux jalons de l’évolution historique de l’informatisation dans les bibliothèques de l’Université. Il s’est ensuite attaché à évaluer l’état actuel de la numérisation dans le réseau des bibliothèques de l’Université par rapport aux développements numériques du secteur. Face à cet état des lieux, il présente des pistes pour accélérer et renforcer la numérisation des bibliothèques. Enfin, pour permettre la mise en œuvre de ce projet, il propose en conclusion des mesures à prendre au niveau de la réorganisation des bibliothèques en termes de locaux et de personnel. [less ▲]

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See detailVariations at different spatial scales of Posidonia oceanica (L.) Delile beds; effects on the physico-chemical parameters of the sediment
Gobert, Sylvie ULg; Kyramarios, Michael; Lepoint, Gilles ULg et al

in Oceanologica Acta (2003), 26(2), 199-207

The biometric parameters (shoot density, length and width of leaves, leaf and epiphyte biomasses, leaf surface) of the P. oceanica meadow present a significant spatial variability at the mesoscale level ... [more ▼]

The biometric parameters (shoot density, length and width of leaves, leaf and epiphyte biomasses, leaf surface) of the P. oceanica meadow present a significant spatial variability at the mesoscale level (100 m2). All the parameters studied, excepting the number of leaves, decrease according to the depth. The horizontal spatial variations (centrifuge and centripetal distributions) reach a maximum in the shallower areas. The analysis of the microstructures (m2) of the meadow has not allowed a relationship to be established between the spatial variations of the biometric parameters and the environmental factors in the sediment (pH, water and organic matter content, red-ox potential, nutrient content). The heterogeneity of the meadow in the Revellata Bay quite probably results from the internal shoot and rhyzome growth dynamics. <br />On the other hand, it appears that the presence of the prairie modifies the physical-chemical characteristics of the sediment. In fact, the sandy patches present different physical-chemical characteristics: lower organic matter, different granulometric and much higher interstitial water nutrient levels, as well as a higher pH and oxydo-reduction potential. [less ▲]

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See detailMarine mammals from the southern North Sea: feeding ecology data from delta C-13 and delta N-15 measurements
Das, Krishna ULg; Lepoint, Gilles ULg; Leroy, Yann et al

in Marine Ecology. Progress Series (2003), 263

The harbour porpoise Phocoena phocoena, grey seal Halichoerus grypus, harbour seal Phoca vitulina and white-beaked dolphin Lagenorhynchus albirostris are regularly found stranded along southern North Sea ... [more ▼]

The harbour porpoise Phocoena phocoena, grey seal Halichoerus grypus, harbour seal Phoca vitulina and white-beaked dolphin Lagenorhynchus albirostris are regularly found stranded along southern North Sea coasts. Occasionally, offshore species such as the fin whale Balaenoptera physalus, the white-sided dolphin L. acutus and the sperm whale Physeter macrocephalus are also found stranded. In order to trace their diet, we measured delta(13)C and delta(15)N in their muscles as well as in 49 invertebrate and fish species collected from the southern North Sea. The delta(15)N data indicate that the harbour seal, grey seal and white-beaked dolphin occupy the highest trophic position, along with ichtyophageous fishes such as the cod Gadus morhua (mean muscle values of 18.7, 17.9, 18.8 and 19.2parts per thousand respectively). The harbour porpoise occupies a slightly lower trophic position (mean delta(15)N value of 16.2parts per thousand), reflecting a higher amount of zooplanktivorous fishes in its diet (mean delta(15)N of 14.7parts per thousand); 2 suckling harbour porpoises displayed a significant delta(15)N enrichment of 2.2parts per thousand compared to adult females. Adult females are delta(15)N-enriched compared to adult male harbour porpoises. Fin whales, sperm whales and white-sided dolphins are C-13-depleted compared to southern North Sea particulate organic matter and species, suggesting that despite regular sightings, they do not feed within the southern North Sea area. [less ▲]

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See detailMarine mammals from Northeast Atlantic: relationship between their trophic status as determined by delta C-13 and delta N-15 measurements and their trace metal concentrations
Das, Krishna ULg; Beans, Cristina; Holsbeek, Ludo et al

in Marine Environmental Research (2003), 56(3),

The relationship between trophic position through delta(13)C and delta(15)N and trace metal concentrations (Zn, Cd, Cu and Hg) was investigated in the tissues of six marine mammal species from the ... [more ▼]

The relationship between trophic position through delta(13)C and delta(15)N and trace metal concentrations (Zn, Cd, Cu and Hg) was investigated in the tissues of six marine mammal species from the Northeast Atlantic: striped dolphin Stenella coeruleoalba, common dolphin, Delphinus delphis. Atlantic white-sided dolphin Lagenorhynchus acutus, harbour porpoise Phocoena phocoena, white beaked-dolphin Lagenorhynchus albirostris, grey seal Halichoerus grypus stranded on French Channel and Irish coasts. White-beaked dolphins, harbour porpoises, white-sided dolphins, common and striped dolphins display the same relative and decreasing trophic position, as measured by delta(15)N values, along both the Irish and French channel coasts, reflecting conservative trophic habits between these two places. Hepatic and renal Cd concentrations were significantly correlated to muscle delta(13)C and delta(15)N values while Hg, Zn and Cu did not. These results suggest that Cd accumulation is partly linked to the diet while other factors Such as age or body condition might explain Hg, Zn or Cu variability in marine mammals. Combined stable isotope and trace metal analyses appear to be useful tools for the study of marine mammal ecology. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailDioxins, furans and dioxin-like PCBs in juvenile harbour porpoises (Phocoena Phocoena) from the North sea
Beans, Cristina; Debacker, Virginie ULg; Jauniaux, Thierry ULg et al

in Organohalogen Compounds (2003)

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See detailCarbon and nitrogen isotopic ratios of the seagrass Posidonia oceanica: Depth-related variations
Lepoint, Gilles ULg; Dauby, Patrick ULg; Fontaine, Michael ULg et al

in Botanica Marina (2003), 46(6), 555-561

Nitrogen (delta(15)N) and carbon (delta(13)C) isotopic compositions of Posidonia oceanica were determined during three seasons along a bathymetric gradient (438 m depth).The delta(15)N values are low (2.2 ... [more ▼]

Nitrogen (delta(15)N) and carbon (delta(13)C) isotopic compositions of Posidonia oceanica were determined during three seasons along a bathymetric gradient (438 m depth).The delta(15)N values are low (2.2+/-0.9%) and variable.They do not show any relation to depth or sampling dates. There is a significant difference between the delta(15)N values of the youngest and the oldest leaves, probably as a result of N resorption and senescing during leaf ageing. The delta(13)C values of young Posidonia leaves vary with depth, showing the relationship between delta(13)C values and primary productivity rate, and the use of a bicarbonate/CO2 mixture as an inorganic carbon source. The delta(13)C values of the oldest P. oceanica leaves are depleted in C-13 compared to those of young leaves. This modification of the C-13 signatures in relation to leaf age is particularly important between 20 and 29 m depth. This modification could be related to photosynthetic rate change during ageing, but also to change in carbohydrate composition and content. [less ▲]

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See detailHeavy metals in marine mammals
Das, Krishna ULg; Debacker, Virginie ULg; Pillet, Stéphane et al

in Vos, Joseph G.; Bossart, Gregory D.; Fournier, Michel (Eds.) et al Toxicology of marine mammals (2003)

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See detailDioxins, furans and co-planar PCBs in juvenile harbour porpoises (Phocoena phocoena) from the Belgian coasts
Beans, Cristina ULg; Das, Krishna ULg; Jauniaux, Thierry ULg et al

Poster (2003)

Dioxins, furans and PCBs are lipophilic anthropogenic contaminants that have found their way into marine food webs and accumulate in top predators such as marine mammals, adding a stress factor to an ... [more ▼]

Dioxins, furans and PCBs are lipophilic anthropogenic contaminants that have found their way into marine food webs and accumulate in top predators such as marine mammals, adding a stress factor to an already vulnerable population. In this study 7 congeners of dioxins (PCDDs), 10 congeners of furans (PCDFs) and 4 congeners of coplanar PCBs (cPCBs) were determined using high resolution gas chromatography and mass spectrometry in the blubber of 19 juvenile harbour porpoises (Phocoena phocoena) stranded along the Belgian North Sea coastline between 1995 and 2001. These results were contrasted with nutritional status (emaciated or not), sex and trophic level (through stable carbon and nitrogen isotope analysis). Mean blubber concentrations of SPCDD/Fs were 12.8 pg/g lw (lipid weight) and mean related toxicity 1.84 pg TEQs/g lw (TEQs = TCDD toxic equivalents). Mean cPCB concentrations were 223,5 pg/g lw and mean related toxicity 4,47 pg TEQs/g lw. The levels detected in these individuals were of the same order as those found in a previous study in the Wadden Sea (Bruhn, 1999). Both sexes show rather similar levels. No significant relationship was observed between stable carbon or nitrogen isotope values and pollutant levels. Concentrations and toxicity show a tendency to be higher in emaciated ndividuals than in nonemaciated ones. This could indicate a possible relationship between the nutritional status of the animals and dioxinlike pollutants (which could participate in weakening the animal). This situation should be further studied on adult individuals in order to obtain a more global view of the possible effects on the population. [less ▲]

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See detailPerfluorooctane sulfonic acids (PFOs) in marine mammals stranded along the North Sea coast.
Van de Vijver, K. I.; Das, Krishna ULg; Van Dongen, W. et al

Poster (2003)

Over the last decades little work has been conducted on the environmental behaviour and effects of perfluorinated organochemicals (FOCs). These chemicals are commonly used as solvents, surfactants ... [more ▼]

Over the last decades little work has been conducted on the environmental behaviour and effects of perfluorinated organochemicals (FOCs). These chemicals are commonly used as solvents, surfactants, cosmetics and are applied in fire foam extinguishers. Recent findings have shown that FOCs (with perfluorooctane sulfonic acid - PFOS - as the most important representative) are detected in organisms living in industrialized as well as in remote areas. The fact that PFOS is hardly biodegradable, clearly accumulates in the liver and blood of top predators and the fact that little information is available on the toxic properties of PFOS, makes this chemical an environmental pollutant of primary concern. In the present study we measured PFOS concentrations in seven marine mammals stranded on the Belgian, French and Dutch North Sea coast between 1994 and 2000. PFOS concentrations were measured in liver and kidney tissue using combined liquid chromatography-mass spectrometry (LC-MS/MS). Detectable PFOS concentrations (up to 820.60 ng/g) were found in harbour porpoises, white-beaked, white-sided and striped dolphins, sperm whales and harbour seals. In fin whale and hooded seal concentrations were below the detection limit of 10 ng/g. PFOS levels in female porpoise livers were significant higher than those in males. The present results show clearly the difference in accumulation pattern of PFOS compared to that of persistent organochlorine chemicals. In order to evaluate the interspecies differences, we developed PFOS-trophic level relationships based on stable nitrogen and carbon isotope ratios. Animals that display the highest trophic positions (highest d15N) have the highest PFOS levels. The different feeding ecology of these species (inshore versus offshore) also seems to contribute to differences in PFOS concentrations. Next to the presentation of PFOS concentrations in marine mammals of the North Sea, the possible toxicological effects of perfluorinated compounds are discussed. [less ▲]

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See detailTrace metals in the harbour porpoise from the North Sea and adjacent areas: relationship with stable isotope measurements, the nutritional status, lesions of the respiratory system and parasitism.
Das, Krishna ULg; Siebert, Ursula; Fontaine, Michaël et al

Conference (2003)

Growing concern has been raised about the status and the long-term viability of the harbour porpoise (Phocoena phocoena) in the North Sea and adjacent areas. Sources of trace metal variations were ... [more ▼]

Growing concern has been raised about the status and the long-term viability of the harbour porpoise (Phocoena phocoena) in the North Sea and adjacent areas. Sources of trace metal variations were investigated using a multidisciplinary approach. Porpoises from the Belgian coasts were compared to individuals from the German North Sea and Baltic coasts, Denmark, Norway and Iceland. Toxicological results (Hg, Zn, Cu, Cd and Se) were confronted to most common pathological findings, namely emaciation, lesions of the respiratory system or parasitism. Influence of diet through stable carbon and nitrogen analysis (d13C and d15N), age and sex have also been considered. As expected, the nutritional status of stranded harbour porpoise from the Southern North Sea is poor compared to by-caught individuals from Norway and Iceland, as reflected by their blubber thickness, weight to length ratio and hepatic to total body mass ratio. The porpoises collected along the Southern North Sea coast display higher Zn and Hg concentrations compared to individuals collected in more preserved areas from the North Atlantic. Moreover, significant Zn, Hg and Se levels were observed with increasing emaciation severity. Porpoises displaying severe bronchopneumonia also have higher Zn concentrations probably due to the association previously described of emaciation and bronchopneumonia. Hg is clearly linked to parasitism. These increasing concentrations are not related to a shrinking of liver mass as it remains unchanged during the emaciation. As a result, hepatic trace metal load increases also. These observations tend to indicate a general redistribution of heavy metals within the organs (muscles to livers), which results from protein catabolism. Such a re-distribution could well be an additional stress for porpoises already experiencing stressful conditions (organochlorines, etc…). In contrast, Cu and Cd were never associated to emaciation. Other parameters such as age class or diet are more likely to be involved. [less ▲]

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See detailTrace elements concentrations in by-caught Norwegian harbour porpoises (Phocoena phocoena): sources of variation and insights in their feeding ecology through stable carbon and nitrogen measurements
Fontaine, Michaël; Siebert, Ursula; Tolley, K. et al

Conference (2003)

Great concern raised from the populations decline observed for the harbour porpoises in the North Atlantic but Norwegian populations remain poorly characterized. Trace elements concentrations (Zn, Cu, Cd ... [more ▼]

Great concern raised from the populations decline observed for the harbour porpoises in the North Atlantic but Norwegian populations remain poorly characterized. Trace elements concentrations (Zn, Cu, Cd, Se, total Hg) have been determined in liver, kidney and muscle of 23 harbour porpoises (Phocoena phocoena) caught in fishing nets along the Norwegian coast. Sources of variation have been examined with a special interest on geographic location and diet modifications analysed through stable isotopes of carbon (δ13C) and nitrogen (δ15N). This study further intend to complete previous feeding ecology knowledge with a combined approach of stable isotopes ratios and metals concentrations as dietary tracers. Norwegian porpoises display mean hepatic concentrations of Zn, Cu and total Hg (96 ± 18; 25 ± 6 ; 15 ± 10 µg.g-1dw respectively) among the lowest in the North-Atlantic. These results suggest that porpoises from this region are less exposed to these metals than others sites such as the North Sea. The low burdens of certain metals (Zn, Cu, Hg) observed make the Norwegian populations suitable to be used as reference level for future ecotoxicological studies on this species. However, renal Cd concentrations (6.7 ± 4.1µg.g-1dw) are twice higher than those from the Southern North Sea. They probably reflect dietary modifications of the porpoises through their range. The low isotopic composition (mean muscle values: d13C=-18.5 ± 0.6 0/00 and δ15N=13.5 ± 1.2 0/00) suggests that Norwegian porpoises feed on more oceanic preys as confirmed by variations of hepatic Hg and renal Cd concentrations. Given that teutophagous marine mammals present higher concentrations of Cd than piscivorous ones. The results obtained lead to the conclusion that the Norwegian porpoises rely on more oceanic squids than those from the North Sea. [less ▲]

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