Advancing salmon welfare from preventing harm to actively promoting positive states is the frontier of aquaculture welfare science. Evidence for salmon positive affect is reshaping how welfare is assessed.
Positive welfare science for farmed salmon represents an important expansion of what aquaculture welfare means. Traditional welfare assessment focused on mortality, disease, and injury — essentially asking whether something bad was happening. Positive welfare science asks whether something good is happening: whether salmon are expressing natural behaviors that reflect positive emotional states. Research using cognitive bias tests — where salmon in better welfare conditions make more optimistic judgments in ambiguous situations — validates the concept that salmon have positive and negative affective states worth measuring and promoting. Environmental enrichment including current jets, varied tank structure, and appropriate light provide stimulation that engages natural behavioral motivation. The welfare journey for farmed salmon is therefore not just eliminating sea lice and improving slaughter — it is creating conditions where individual fish can express the behavioral complexity that reflects their evolutionary history as active, capable animals.