Sea lions and fur seals face significant mortality and welfare harm from entanglement in fishing gear and bycatch, making fisheries management and gear modification critical for reducing the suffering of these charismatic marine mammals.
Sea lion entanglement represents a welfare problem with dual causes: passive entanglement in discarded or lost fishing gear, and active entanglement when animals attempt to access fishing gear as a food source. The welfare consequences of entanglement include progressive deep tissue wounds as constricting material cuts through skin and muscle during growth, chronic pain, impaired movement and hunting ability, and eventual starvation or septicemia from infected wounds. Marine mammal rescue teams can remove gear from stranded entangled animals, but many entangled sea lions are never found or cannot be approached. Reducing entanglement requires a combination of fisheries gear modification to reduce entanglement risk, improved disposal of fishing gear to reduce ghost gear in the marine environment, and fishery management that reduces the economic incentive for sea lions to raid gear by ensuring adequate prey availability.