Abstrakt

Determination of tuna spawning areas off the Ivory Coast: Contribution of satellite imagery.

Jean-Baptiste Kassi*, Yannick Koko Gnahoua, Jacques Andre Tiemele

Tuna is one of the pelagic species whose landing on the Ivorian continental shelf is spectacular. However, given the threats facing this species, we have conducted this study in order to contribute to the safeguarding and sustainable management of this threatened fish species. The study is based on the analysis of oceanic parameters that determine the potential spawning areas of tunas in Ivory Coast. To do this, remote sensing data from MODIS, SMOS and ERA Interim sensors have been used to estimate the temperature, the sea surface salinity and the seawater turbulence. Tuna stock data from the Aquaculture and Fisheries Department of Côte d'Ivoire were used. The methodology used is a multi-criteria analysis based on the three oceanic parameters of sea surface turbulence, temperature and salinity, which allowed to highlight the potential spawning areas of tunas as a function of the seasons of the year. The results showed that the preferred periods for tuna spawning cover from December to June with areas of low turbulence, salinity between (34 and 35 psu) and temperatures above 26°C between latitudes 0° and 3°N.