Dissolved oxygen levels in aquaculture systems directly determine fish survival and welfare. Understanding oxygen management is fundamental to improving farmed fish welfare outcomes.
Dissolved oxygen management is one of the most fundamental determinants of welfare in aquaculture systems. Fish experiencing hypoxia exhibit characteristic stress behaviours including surface gulping, reduced activity, and grouping near aeration equipment. Chronic mild hypoxia reduces immune function, feed conversion, and growth while causing ongoing physiological stress. Severe hypoxia causes acute suffering and rapid mass mortality. Welfare-conscious aquaculture requires continuous dissolved oxygen monitoring with automated alerts and backup aeration capacity to prevent equipment failure events. The relationship between stocking density and oxygen demand means that higher densities require proportionally greater investment in aeration infrastructure to maintain equivalent welfare standards. Investment in robust oxygen monitoring and management infrastructure is both a welfare imperative and an economic necessity given the cost of mortality events.