The vaquita porpoise, a silver-coloured porpoise with wide, panda eyes, is found only in Mexico. It is the most critically endangered sea mammal on the planet. Its survival threatened by a deadly clash of interests between fishing and conservation. The totoaba's swim bladder is considered a delicacy in China, and can fetch tens of thousands of dollars on the black market. To protect the vaquita, all gillnets are banned in the upper Gulf. However, they are widely used, even by fishermen with permits for halibut or prawns. The Mexican government recently announced new measures aimed at saving the critically endangered vaquita porpoise. The regulations aim to improve surveillance and supervision of fishing in the northern Gulf of California.