Tilapia is the second most farmed fish globally, produced in over 140 countries. Developing welfare standards for this enormously important species has significant impact for billions of fish.
Tilapia welfare in intensive aquaculture deserves serious attention given the sheer number of individuals involved. Chronic crowding stress suppresses immune function and increases susceptibility to bacterial and parasitic disease, causing suffering that is often invisible to producers focused on growth metrics. Aggression at feeding — tilapia are territorial and competitive — causes fin erosion and scale damage in densely stocked systems. Hormonal treatment of fry to produce all-male monosex populations is standard practice; while the welfare implications of this at the individual fish level require further research, the practice raises ethical questions. Humane slaughter of tilapia remains poorly regulated — live chilling and asphyxiation in air are common practices. Developing and mandating welfare standards for tilapia aquaculture at scale is an urgent priority.