The stunning of farmed fish before slaughter is a critical welfare issue, as fish are sentient beings capable of experiencing pain and stress during slaughter processes that often lack any stunning.
Fish welfare at slaughter represents one of the largest-scale animal welfare failures given the billions of individuals involved. The scientific consensus that fish feel pain makes unstunned slaughter by asphyxiation or live chilling ethically unacceptable. Progress is possible - salmon slaughter practices have improved significantly in Norway through regulation. Consumer pressure, certification schemes, and corporate welfare commitments are driving gradual improvement, but most farmed fish still die without effective stunning.