Seasonal and inter-annual variability in abundance of the main tropical tunas in the EEZ of Côte d’Ivoire (2000-2019)

The seasonal and inter-annual variability in abundance of the main “local tropical tuna resources” EEZ Côte d'Ivoire was analysed with catch effort data from French Spanish purse seiners over period 2000–2019. A spatio-temporal model developed by Thorson et al. (2020a) used to estimate indices for tunas commercial category (<10 kg and> = 10 kg, which correspond roughly maturity stage: immature mature respectively), fishing mode (free school sets FAD sets). Furthermore, we decomposed time series into intrinsic functions using CEEMDAN algorithm. decomposition procedure made it possible filter out noise signal extract components indices. generalized additive (GAM) applied reveal influences environmental factors on species distribution. Biological interpretations were effects variables this discussed. Our results suggest that there are two seasons d'Ivoire. It also found yellowfin abundant between first second quarter year while best season skipjack occurs third fourth quarter. In addition, observed a considerable change area.