| 1. |
- Hansson, T., et al.
(författare)
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Long-term monitoring of the health status of female perch (Perca fluviatilis) in the Baltic Sea shows decreased gonad weight and increased hepatic EROD activity
- 2006
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Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X. ; 79:4, s. 341-355
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Tidskriftsartikel (refereegranskat)abstract
- Annual investigations of the health status of female perch (Perca fluviatilis) were performed during 8-13 years in order to detect long-term, large-scale changes in the Baltic Sea. These background data are also meant to be used as baselines in recipient investigations at various point sources in the Baltic Sea. Fish were sampled at three coastal sites in Sweden: two in the Baltic Proper (since 1988) and one in the Bothnian Bay (since 1993). In all, 19 biochemical, physiological and histopathological variables were measured. By reflecting central functions of life, such as red blood cell functions, immune defence, liver function, biotransformation processes, intermediary metabolism, ion balance, and reproduction, the selected variables give a good picture of the health status of the fish. The most important observations were strong trends towards decreased gonadosomatic index (relative gonad size) and increased hepatic EROD activity in female perch in the Baltic Proper. Most of the other variables varied little between the years. The reduced gonad size and the EROD induction indicate that factors in the environment, e.g. the occurrence of pollutants, affect important physiological functions, such as reproduction and biotransformation processes, in fish even in a reference area in the Baltic Proper. It is urgent to make further studies in order to identify which pollutant(s) or other possible cause(s) are responsible for the observed biological effects. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Ronisz, Dan, et al.
(författare)
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Thirteen years of monitoring selected biomarkers in Eelpout (Zoarces viviparus) at reference site in the Fjällbacka Archipelago on the Swedish West Coast
- 2005
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Ingår i: Aquatic Ecosystem Health & Management. - : Michigan State University Press. - 1463-4988 .- 1539-4077. ; 8:2, s. 175-184
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Tidskriftsartikel (refereegranskat)abstract
- Several biomarkers in female and male eelpout (Zoarces viviparus) were measured at Fjällbacka, a reference site on the Swedish west coast from 1989 to 2001. Standardised procedures for sampling and measurements were used. Some of the biomarkers were largely stable through the years, for example, condition factor, blood plasma chloride concentration, white blood cell count, percentage of lymphocytes, activities of glutathione-S-transferase and glutathione reductase. Others showed greater variations but not significant trends, for example, percentage of granulocytes and activity of catalase and ethoxyresorufin-O-deethylase activity. Three variables in female eelpout showed a statistically significant downward trend from 1989 to 2001, hematocrit, body weight and length. The change in hematocrit was probably related to decreased stress due to improved sampling techniques, but the reason for changes in weight and length remain unknown. There is a need to evaluate the area for pollutants. The results indicate that there have not been any major large-scale changes in the aquatic environment affecting the fish health at the investigated site
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| 3. |
- Sandstrom, O., et al.
(författare)
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Three decades of Swedish experience demonstrates the need for integrated long-term monitoring of fish in marine coastal areas
- 2005
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Ingår i: Water Quality Research Journal of Canada. - 1201-3080. ; 40:3, s. 233-250
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Tidskriftsartikel (refereegranskat)abstract
- The first attempts to monitor coastal fish in Sweden were made in the 1960s and 1970s. Ecological, physiological, biochemical and environmental chemistry data were collected in separate projects. When the National Marine Monitoring Programme was revised in 1992, a new strategy was introduced for assessments of long-term trends in coastal fish communities. Annual integrated monitoring of contaminants, biomarkers and population and community indicators of ecosystem health was started in selected areas using common sentinel species. Data from one monitoring area at the coast of the Baltic proper are analyzed in this paper. The results have shown a shift in fish community structure indicating changes in ecosystem productivity. Trends have been detected in growth rate (positive) and relative gonad size (negative) in perch (Perca fluviatilis), suggesting a metabolic disturbance according to the predictive response model developed for interpretations. One factor which may have contributed to the reduced GSI was a decrease in mean age of sampled fish during the period of study. Chemical exposure was indicated by a 3-fold increase of EROD activity during the monitored 15-year period. However, concentrations of most measured contaminants in perch have decreased during the same period. The experience of the integrated approach has shown that a tentative analysis of cause and environmental significance could be made, improving the assessment, but there still remain unsolved questions to be answered in follow-up studies. The analysis has also shown the importance of long-term monitoring at several levels of biological organization to distinguish between natural variation and low-level effects on ecosystems.
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