Spawning Environmental Window of Sardina Pilchardus Along the Atlantic Coast of Northwest Africa (21°N - 32°N)

In spite of the ecological and socio-economic importance of sardine (Sardina pilchardus), its early life history studies in Moroccan coast has been limited. Through cooperation by Moroccan and Japanese scientists, the spawning environmental conditions have been investigated. The study area is located between Cape Blanc (21°N) and Cape Cantin (32°N) in the Eastern Atlantic coast and analyzed data were collected during surveys on board the R/V ‘AtlantNiro’ from 1994 to 1999. The time series were retrospectively analyzed and nonparametric multivariate analysis including generalized additive model (GAM) were applied to extract the spawning environmental window (SEW) of sardine.  We found spatial correspondence of sardine eggs to temperature less than 18 to19°C, mid-high Chlorophyll-a and zooplankton biomass. Found positive relationship among egg density, Chlorophyll-a and zooplankton biomass can be interpreted as the result of physical retention of the eggs and planktons through time series. The scale of the SEW was variable through time series probably because of coastal upwelling in the area. Continuous monitoring and investigation of changes of SEW along the spatio-temporally dynamics of oceanography will produce the mechanism and impact of the environmental variability upon the recruitment of sardine and will contribute to the sustainability of Moroccan sardine fisheries.