Could a Fish Drown? Understanding the unique respiratory system of fish, which utilizes gills for oxygen extraction from water, is crucial. When oxygen levels in water decline, fish experience physiological and behavioral responses such as reduced oxygen uptake, impaired metabolism, gasping, and gill flaring. Environmental factors like water quality and dissolved oxygen levels significantly influence their respiration. Oxygen depletion can lead to fish kills with ecological consequences. Technical solutions such as oxygenation systems can help mitigate oxygen depletion, ensuring fish survival and aquatic ecosystem health.