During my PhD, the life cycle of Paracartia grani, a calanoid copepod belonging to the Acartiidae family was determined in Thau lagoon. Indeed, the copepod involvement in the life cycle of the parasite Marteilia refringens affecting the bivalve productions is suspected.
From April to January, the copepod is found in the water column while from February to early April it remains in the sediment as diapausing eggs. The analysis of the population structure (size spectrum, contribution of developmental stages and sex ratio) has revealed that there are in between 6 and 9 generations per year. The study of the influence of three environmental parameters (temperature, salinity and chlorophyll a concentration) on the dynamic nesting species indicated that P. grani egg production was mainly governed by temperature and its rapid increase in spring could trigger the hatching of diapause eggs.
The second objective of this study aimed to describe the dynamics of the parasite M. refringens in P. grani, and in the bivalves Mytilus galloprovincialis and Ruditapes decussatus in the Thau lagoon. Histological and in situ hybridization analysis allowed describing the different forms of the parasite in these three species. Our study has allowed clarifying interaction between copepod, parasite and mussel but not elucidate completely M. refringens life cycle. Questions remain, especially regarding way of transmission of parasite from copepods to mussels and the potential impact of the parasite on the copepod itself.
The electronic version of my thesis is available here
During my post-doctoral position at the Maurice-Lamontagne Institute, I developped an habitat modelling of 4 copepod species with general additive mixed models and a depth-integrated database (14 years of sampling), in the aim to evaluate changes in productivity (abundance) and occurrence of these species in the Northwest Atlantic Ocean at spatial and temporal scale in context of global warming.
From April to January, the copepod is found in the water column while from February to early April it remains in the sediment as diapausing eggs. The analysis of the population structure (size spectrum, contribution of developmental stages and sex ratio) has revealed that there are in between 6 and 9 generations per year. The study of the influence of three environmental parameters (temperature, salinity and chlorophyll a concentration) on the dynamic nesting species indicated that P. grani egg production was mainly governed by temperature and its rapid increase in spring could trigger the hatching of diapause eggs.
The second objective of this study aimed to describe the dynamics of the parasite M. refringens in P. grani, and in the bivalves Mytilus galloprovincialis and Ruditapes decussatus in the Thau lagoon. Histological and in situ hybridization analysis allowed describing the different forms of the parasite in these three species. Our study has allowed clarifying interaction between copepod, parasite and mussel but not elucidate completely M. refringens life cycle. Questions remain, especially regarding way of transmission of parasite from copepods to mussels and the potential impact of the parasite on the copepod itself.
The electronic version of my thesis is available here
During my post-doctoral position at the Maurice-Lamontagne Institute, I developped an habitat modelling of 4 copepod species with general additive mixed models and a depth-integrated database (14 years of sampling), in the aim to evaluate changes in productivity (abundance) and occurrence of these species in the Northwest Atlantic Ocean at spatial and temporal scale in context of global warming.
Other research interests:
- Populations dynamics of zooplankton species, especially copepods
- Reproductive strategies (resting eggs, diapause, advection)
- Impacts of climate changes on the distribution of zooplankton species at local and global scales
- Intraguild competition
- Involvment of copepods in parasite life cycle (Marteiliosis disease)
- Importance of zooplankton in marine food-webs