A Long Term Ecological Research Program -GUADALQUIVIR_LTER 1997-2022- has been maintained since 1997 at the Guadalquivir estuary. The temporal and spatial evolution of abundances and biomasses of the aquatic community species -plankton, fish, and crustacean- is monitored monthly since 26 years ago (1997 to present). Community data is resolved at different levels of the ecosystem -individuals, populations, and communities- and completed with their corresponding water environmental data -salinity, temperature, turbidity, dissolved oxygen, nutrients, pH, among others- as well as detailed information on trophic structure and biology of the main species. Since 2021 a new Spanish Science Agency project is working together with Guadalquivir-LTER on the socio-ecology of the region, management, and cooperation among different stakeholders.