This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Structure and spatio-temporal dynamics of the artisanal small-scale fisheries at the future MPA o... more Structure and spatio-temporal dynamics of the artisanal small-scale fisheries at the future MPA of "Taza" (Algerian coast, SW Mediterranean)
Abstract This summary of the Senegalese coastal and marine environment is based on both reviews o... more Abstract This summary of the Senegalese coastal and marine environment is based on both reviews of recent scientific knowledge and new data by the authors. The coastal and marine habitats, environmental conditions, and its biodiversity are described. Climate change and the major threats to biodiversity and habitats are then discussed. Senegal’s coasts are affected by a number of environmental problems, including pollution, coastal erosion, coastal flooding, soil and water salinization, mangrove degradation, and a reduction in fish stocks. Fisheries play an important socioeconomic role for Senegal and a focus on fisheries resources is presented. Finally, management regimes for coastal ecosystems, biodiversity, and fishery conservation are presented.
Abstract This summary of the Senegalese coastal and marine environment is based on both reviews o... more Abstract This summary of the Senegalese coastal and marine environment is based on both reviews of recent scientific knowledge and new data by the authors. The coastal and marine habitats, environmental conditions, and its biodiversity are described. Climate change and the major threats to biodiversity and habitats are then discussed. Senegal’s coasts are affected by a number of environmental problems, including pollution, coastal erosion, coastal flooding, soil and water salinization, mangrove degradation, and a reduction in fish stocks. Fisheries play an important socioeconomic role for Senegal and a focus on fisheries resources is presented. Finally, management regimes for coastal ecosystems, biodiversity, and fishery conservation are presented.
HAL (Le Centre pour la Communication Scientifique Directe), 2015
International audienceAssessing water quality is an essential prerequisite for good water body ma... more International audienceAssessing water quality is an essential prerequisite for good water body management. In this respect, fish are excellent sentinel species and have proven their usefulness for more than a century. Although the initial use of fish was restricted to acute toxicity testing, recent developments of methodologies, equipment, techniques, and concepts have led to integrated studies that encompass molecular, physiological, and ecological knowledge and tools. Efforts have been made to link these different levels of organization, and the results largely contributed to our understanding of the mechanism of action of chemicals in a complex set of environmental stressors and conditions
Over the past decade, the distribution of harbour porpoises Phocoena phocoena has undergone a sou... more Over the past decade, the distribution of harbour porpoises Phocoena phocoena has undergone a southward shift in the North Sea, which has led to an increase in the number of stranded porpoises in its southern part. Since the changes in distribution and relative abundance of porpoises may be linked to the changes in prey availability, the aim of the present work was to investigate whether any changes in the feeding habits of harbour porpoises along the North Sea occurred in the past decade. The diet of harbour porpoises stranded along the southern North Sea (northern France and Belgian coast) was assessed through 3 complementary methods: stomach content analysis, stable isotopes (carbon and nitrogen) analysis determined from muscle samples, and fatty acids analysis determined from blubber samples. Fatty acid patterns and stable isotope values from 52 porpoises were compared to 14 potential prey species collected from the southern North Sea. Our results showed that the diet of porpoises along the southern North Sea comprises fish species that are among the most abundant and widely distributed in the area, except for the sardine Sardina pilchardus that appeared to be a new potential prey. Moreover, our results suggested that the decline in sandeel (Ammodytidae) in the northern parts of the North Sea along with the re-invasion of the southern North Sea by sardine species might affect the distribution of harbour porpoises.
To evaluate the impact of metamorphosis on the vertical distribution and feeding activity of sole... more To evaluate the impact of metamorphosis on the vertical distribution and feeding activity of sole, Solea solea, larvae passing from offshore spawning grounds to the Bay of Vilaine, sampling series at fixed stations were carried out in April 1991 and April 1993 at depths from 50 to 30 m. Comparisons between plankton and bottom sampling series indicated differences in vertical distribution of larvae in pre-metamorphic and metamorphic steps. Metamorphosing larvae displayed a tendency to concentrate in the lower part of the water column, mainly during the day. Gut contents, analysed for prey identification, fullness index and carbon content, indicated that metamorphosing larvae fed mostly on plankton. Variations in fullness index were observed not only during the day, but also depended on tide and wind-induced mixing conditions. Larvae sampled in mixed spring-tide waters had highly variable carbon estimates, resulting in unclear diel activity. More larvae fed actively at neap-tide, which allowed the observation of a diurnal feeding activity through hourly changes in carbon estimates. It is concluded that immigrating sole were not yet able to settle but prepared themselves for demersal life (i) without undergoing starvation and (ii) by modifying the patterns of vertical distributions. The presence of a larval swimbladder suggests they can adjust their vertical movements, depending on tidal cycles, which could in turn favour coastal accumulation of metamorphosing larvae and pulses of new settlers entering the nursery grounds.
Fish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we c... more Fish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we can learn from stable isotope analysis
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Structure and spatio-temporal dynamics of the artisanal small-scale fisheries at the future MPA o... more Structure and spatio-temporal dynamics of the artisanal small-scale fisheries at the future MPA of "Taza" (Algerian coast, SW Mediterranean)
Abstract This summary of the Senegalese coastal and marine environment is based on both reviews o... more Abstract This summary of the Senegalese coastal and marine environment is based on both reviews of recent scientific knowledge and new data by the authors. The coastal and marine habitats, environmental conditions, and its biodiversity are described. Climate change and the major threats to biodiversity and habitats are then discussed. Senegal’s coasts are affected by a number of environmental problems, including pollution, coastal erosion, coastal flooding, soil and water salinization, mangrove degradation, and a reduction in fish stocks. Fisheries play an important socioeconomic role for Senegal and a focus on fisheries resources is presented. Finally, management regimes for coastal ecosystems, biodiversity, and fishery conservation are presented.
Abstract This summary of the Senegalese coastal and marine environment is based on both reviews o... more Abstract This summary of the Senegalese coastal and marine environment is based on both reviews of recent scientific knowledge and new data by the authors. The coastal and marine habitats, environmental conditions, and its biodiversity are described. Climate change and the major threats to biodiversity and habitats are then discussed. Senegal’s coasts are affected by a number of environmental problems, including pollution, coastal erosion, coastal flooding, soil and water salinization, mangrove degradation, and a reduction in fish stocks. Fisheries play an important socioeconomic role for Senegal and a focus on fisheries resources is presented. Finally, management regimes for coastal ecosystems, biodiversity, and fishery conservation are presented.
HAL (Le Centre pour la Communication Scientifique Directe), 2015
International audienceAssessing water quality is an essential prerequisite for good water body ma... more International audienceAssessing water quality is an essential prerequisite for good water body management. In this respect, fish are excellent sentinel species and have proven their usefulness for more than a century. Although the initial use of fish was restricted to acute toxicity testing, recent developments of methodologies, equipment, techniques, and concepts have led to integrated studies that encompass molecular, physiological, and ecological knowledge and tools. Efforts have been made to link these different levels of organization, and the results largely contributed to our understanding of the mechanism of action of chemicals in a complex set of environmental stressors and conditions
Over the past decade, the distribution of harbour porpoises Phocoena phocoena has undergone a sou... more Over the past decade, the distribution of harbour porpoises Phocoena phocoena has undergone a southward shift in the North Sea, which has led to an increase in the number of stranded porpoises in its southern part. Since the changes in distribution and relative abundance of porpoises may be linked to the changes in prey availability, the aim of the present work was to investigate whether any changes in the feeding habits of harbour porpoises along the North Sea occurred in the past decade. The diet of harbour porpoises stranded along the southern North Sea (northern France and Belgian coast) was assessed through 3 complementary methods: stomach content analysis, stable isotopes (carbon and nitrogen) analysis determined from muscle samples, and fatty acids analysis determined from blubber samples. Fatty acid patterns and stable isotope values from 52 porpoises were compared to 14 potential prey species collected from the southern North Sea. Our results showed that the diet of porpoises along the southern North Sea comprises fish species that are among the most abundant and widely distributed in the area, except for the sardine Sardina pilchardus that appeared to be a new potential prey. Moreover, our results suggested that the decline in sandeel (Ammodytidae) in the northern parts of the North Sea along with the re-invasion of the southern North Sea by sardine species might affect the distribution of harbour porpoises.
To evaluate the impact of metamorphosis on the vertical distribution and feeding activity of sole... more To evaluate the impact of metamorphosis on the vertical distribution and feeding activity of sole, Solea solea, larvae passing from offshore spawning grounds to the Bay of Vilaine, sampling series at fixed stations were carried out in April 1991 and April 1993 at depths from 50 to 30 m. Comparisons between plankton and bottom sampling series indicated differences in vertical distribution of larvae in pre-metamorphic and metamorphic steps. Metamorphosing larvae displayed a tendency to concentrate in the lower part of the water column, mainly during the day. Gut contents, analysed for prey identification, fullness index and carbon content, indicated that metamorphosing larvae fed mostly on plankton. Variations in fullness index were observed not only during the day, but also depended on tide and wind-induced mixing conditions. Larvae sampled in mixed spring-tide waters had highly variable carbon estimates, resulting in unclear diel activity. More larvae fed actively at neap-tide, which allowed the observation of a diurnal feeding activity through hourly changes in carbon estimates. It is concluded that immigrating sole were not yet able to settle but prepared themselves for demersal life (i) without undergoing starvation and (ii) by modifying the patterns of vertical distributions. The presence of a larval swimbladder suggests they can adjust their vertical movements, depending on tidal cycles, which could in turn favour coastal accumulation of metamorphosing larvae and pulses of new settlers entering the nursery grounds.
Fish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we c... more Fish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we can learn from stable isotope analysis
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