Introduction: The North Pacific of Costa Rica is a diverse and productive region; however, we have a poor understanding of the status of marine resources and fisheries dynamics operating in this region, specifically the artisanal fishery. Objective: This study characterized the spatio-temporal dynamics of the artisanal fishery in the Gulf of Santa Elena, one of the main fishing grounds of the North Pacific of Costa Rica. Methods: We analyzed data collected by the Instituto Costarricense de Pesca y Acuicultura (INCOPESCA) and sales invoice obtained from fishing landing sites for the period 2010-2019. Results: There was high variation in the biomass landed , however, total catch per unit effort (CPUE; kg / day) did not decreased significantly. Overall, there was a lower CPUE during upwelling months (Decemver-April) relative to non-upwelling months (May-November). A total of 42 species of commercial species were reported, in which the spotted rose snapper (Lutjanus guttatus; 22% of the biomass), the Pacific red snapper (L. peru; 18% of the biomass), groupers (Epinephelus spp.; 15% of the biomass) and octopuses (Octopus spp., 13% of the biomass) contributed to the highest biomass reported for the study period. Conclusion: This study showed that CPUE of commercially important species landed in the Gulf of Santa Elena has not declined significantly over the last decade (2010-2019); however, there was a decline of CPUE during the upwelling season across years. Given the lack of landing statistics data for artisanal fisheries, the analysis of fishing sales invoice represents a valuable managemen tool to monitor population trends of marine resources.

Keywords: fisheries dynamics, artisanal fleet, seasonal change, upwelling, Central America