Vaquita still hanging on

The vaquita porpoise is easily the most endangered marine mammal on Earth. The smallest of the porpoises, the chunky little cetacean with black rings around its eyes was nicknamed "little cow" by local fishermen in Gulf of California a long time ago.  Now a lot of fishermen (though certainly not all) nickname it something a lot harsher and wish it would vanish so they could poach totoaba fish, whose bladders are worth tens of thousands of dollars each. (To be fair, even fishermen who want to catch something else are under the gun, literally, from drug smugglers - the bladders are worth as much as the drugs.)
Extinction is almost here. The estimates of numbers have been down as low as 12, which isn't a viable population in the wild even under perfect conditions. I wouldn't have been surprised at all if it hit 0 this year.
And yet, the species has been hanging on, just barely. Every sighting is cherished and every calf is cause for a champagne celebration among conservationists, so an expedition sighting 6 animals was very good news.  The latest estimate of 30 offers, if not celebration, at least hope.