The vaquita (Phocoena sinus) is a rare species of porpoise endemic to the northern part of the Gulf of California. It is listed as critically endangered because the estimated number of individuals dropped below 100 in 2014, putting it in imminent danger of extinction. Since the baiji (Lipotes vexillifer) is believed to have gone extinct by 2006, the vaquita has taken on the title of the most endangered cetacean in the world.