Mbaye B.C., Ndoye S., Capet X., Machu Eric. (2017). Influence of fine scale processes on fish larvae retention in the Senegalese upwelling region [résumé]. In :
Brehmer Patrice (ed.), Ba B. (ed.), Kraus G. (ed.). International conference ICAWA 2016 : extended book of abstract : the AWA project : ecosystem approach to the management of fisheries and the marine environment in West African waters. Dakar : SRFC/CSRP ; IRD, p. 83. ICAWA : International Conference AWA, 3., Dakar (SEN), 2016/12/13-15. ISBN 978-2-9553602-0-5.
Titre du document
Influence of fine scale processes on fish larvae retention in the Senegalese upwelling region [résumé]
Année de publication
2017
Type de document
Colloque
Auteurs
Mbaye B.C., Ndoye S., Capet X., Machu Eric
In
Brehmer Patrice (ed.), Ba B. (ed.), Kraus G. (ed.), International conference ICAWA 2016 : extended book of abstract : the AWA project : ecosystem approach to the management of fisheries and the marine environment in West African waters
Source
Dakar : SRFC/CSRP ; IRD, 2017,
p. 83 ISBN 978-2-9553602-0-5
Colloque
ICAWA : International Conference AWA, 3., Dakar (SEN), 2016/12/13-15
Mesoscale physical processes can affect the fate and distribution of fish eggs and larvae by aggregating and retaining them in favorable habitats or spreading them away to inappropriate areas. Here we examined the effect of fine scale processes on fish larval retention through a biophysical model of the early life stages of Sardinella aurita taken as an example within the Senegalese upwelling region. A set of 3 ROMS configurations is used from coarser (~ 9km, 7.5km) to finer (~ 2km) resolution. The ICHTHYOP individual based model is then forced by the different model experiments. To take into account more realistic physical forcing, the finer resolution configuration was used to test the effect of synoptic winds and tides. We first show that a finer resolution of physical processes provides a retention twice stronger. In addition that experiment shows 2 contrasted results in the region which differ from previous modelling work : 1) the northern domain considered so far as a low retention area displays high retention values and 2) a better resolution of the hydrodynamic of the Senegalese shelf modifies significantly the retention spatial patterns in the southern area although the seasonality remains similar. Simulation using synoptic winds and tidal forcing suggest a reduction of retention induced by a higher larval mortality due to enhanced export transport and stronger lethal temperature exposure.
Plan de classement
Sciences du milieu [021]
;
Ressources halieutiques [040]
