Estuary ecosystems

Biology of fish   |  Ecology of fish communities  |  Halieutic ecology  Importance of Marine Protected Areas


Estuaries, transition zones between land and sea, are complex environments with highly diversified  communities. The reduction or interruption of fresh water input results in higher salinity in  upstream zones and the inversion of the salinity gradient. Few species manage to live in the saltiest zones of hypersaline estuaries. Those who do present remarkable physiological adaptations which may involve modifications in reproduction or growth.
This is the case for two species found upstream in the Sine Saloum estuary in Senegal, the tilapia, Sarotherodon melanotheron, and the ethmalose, Ethmalosa fimbriata, in extreme conditions of salinity (130 psu). Understanding the responses of individuals, populations, and communities of fishes to natural and/or anthropogenic disturbances, has at stake the conservation of resources, on both national and international levels. In this context, IRD and its partners are pursuing a regional research project in West Africa: Senegal, Mauritania, Gambia and Guinea-Bissau.

consommation de poissons