The rapid decline in oxygen levels poses significant risks to aquatic ecosystems and the organisms that depend on them. Disrupted biological and chemical processes threaten species across food webs, from microscopic life to larger marine animals like fish and sharks. Marine mammals, despite breathing air at the surface, face indirect impacts such as reduced prey availability and habitat degradation. Additionally, oxygen loss can weaken Earth's climate regulation mechanisms, amplifying other environmental challenges. Scientists warn that some changes may persist for centuries and could be irreversible within human lifetimes, pushing the planet into an 'unsafe space.'