Sea otters are affected by entanglement in lost fishing gear, plastic debris, and boat engine intakes that cause injuries, drowning, and chronic welfare impacts in recovering populations.
Sea otter entanglement injuries create a distinctive welfare challenge because otters depend on forelimb dexterity for grooming their fur - the primary thermal insulation mechanism. Flipper injuries that reduce grooming capacity indirectly compromise thermoregulation even without directly impeding swimming. A nutritionally marginal otter with compromised grooming faces compounding welfare deficits. The small population size of California sea otters means that each individual's welfare matters disproportionately to population viability, reinforcing the case for active debris removal and entanglement prevention programs.