California sea lions face dual welfare threats from fishing gear entanglement and domoic acid poisoning from harmful algal blooms, both causing serious suffering in wild populations.
Sea lions experiencing domoic acid toxicosis suffer acute neurological symptoms including severe seizures that are visible to observers as highly distressing. Brain damage from severe poisoning causes permanent behavioral abnormalities that prevent rehabilitation and release. Entanglement wounds progress from initial lacerations to deep, infected grooves as sea lions grow within constricting loops, causing months of suffering before death or discovery. Both threats are influenced by human activity: harmful algal bloom frequency is increasing with ocean warming driven by climate change, while entanglement is a direct result of fishing and plastic waste. Rescue and rehabilitation provides welfare relief for individuals while advocacy addresses systemic causes.