Tilapia is the most widely farmed fish globally outside China. Its welfare in intensive aquaculture systems is poorly understood by most consumers despite enormous production scales.
Tilapia welfare suffers from the assumption that a hardy fish is an unfeeling fish. Tilapia can tolerate low oxygen, high ammonia, and crowded conditions that would kill many other species, but tolerance of harsh conditions does not equate to indifference to them. Chronic stress from overcrowding, poor water quality, and repeated handling causes measurable physiological stress responses in tilapia. The extraordinarily low cost of farmed tilapia reflects minimal welfare investment. As a fish consumed at huge scale globally, even small improvements in tilapia welfare standards would benefit an enormous number of individuals.