Transporting live fish — for stocking, sales, or processing — causes significant stress and mortality if not managed carefully, making transport welfare a significant welfare challenge in aquaculture.
Fish transport causes multiple simultaneous welfare stressors: crowding, handling, oxygen reduction, unfamiliar water chemistry, and motion. The physiological stress response — elevated cortisol, immune suppression, exhaustion — is measurable and causes real welfare harm. Good transport practices significantly reduce this harm: appropriate anaesthesia, adequate oxygen, careful loading and unloading, and minimal transport duration all matter. For live fish sold in markets, the welfare of fish held in display tanks for extended periods before purchase is an additional concern that has received little regulatory attention.