Sea lions and fur seals interact with fishing operations in ways that cause welfare harm through entanglement, illegal killing, and depletion of prey resources.
Sea lion and fur seal welfare involves both direct harm (shooting, entanglement) and indirect harm (prey depletion causing pup starvation). Pups that cannot be fed adequately during nursing are weaned too early and arrive at sea lacking the body condition to survive foraging. Mass mortality events linked to fish population crashes can kill thousands of pups in single seasons. The welfare case for sustainable fisheries management overlaps directly with seal population welfare — abundant prey means well-nourished pups and reduced conflict with fishers.