Impacto da expansão das camadas mínimas de oxigénio na ecologia vertical de tubarões e lulas oceânicas

Orador: Rui Rosa

Climate change is one of the major threats our world is facing over the current century. Driven mainly by a continuous rise in carbon dioxide (CO2), climate change is manifested through three main stressors in the marine environment, namely ocean warming (OW), ocean acidification (OA) and ocean deoxygenation (OD). Regarding the latter, it is associated with temperature-driven declines in oxygen solubility, strengthened stratification of seawater masses and increased microbial oxygen consumption.  In the oceanic realm, the aforementioned physical processes and the sinking of eutrophication-related “marine snow”, drive the formation and horizontal expansion/shoaling of oxygen minimum zones (OMZs), which are dramatically increasing worldwide. Here I discuss the impacts of the this “deadly-trio” in the vertical ecology of marine top predators, sharks and squids, that thrive above and within the OMZs environment of the Eastern Tropical Atlantic and Eastern Tropical Pacific, respectively. The potential cascading effects in the pelagic food webs and increased vulnerability to fisheries are also discussed.