The vaquita is the world's most endangered marine mammal, with fewer than 10 individuals remaining. Its welfare crisis is unique — almost entirely caused by illegal fishing for the critically endangered totoaba fish.
Vaquita welfare operates at the extreme end of extinction risk, where individual welfare and species survival are completely synonymous — each individual is simultaneously irreplaceable and at immediate risk. Gillnet entanglement causes drowning deaths that, in a species capable of complex cetacean cognition, involve awareness and distress before oxygen deprivation ends consciousness. With fewer than 10 individuals remaining, every mortality event is catastrophic both for the individual and for the species. The failed 2017 rescue attempt illustrated the welfare challenge of even well-intentioned intervention: vaquitas are so sensitive that capture itself poses lethal risk. The welfare tragedy of the vaquita is that its suffering is caused almost entirely by the demand for another critically endangered species' body part — a cascade of human-driven extinctions where the illegal wildlife trade destroys two species simultaneously.