After long suffering from the effects of human activity at its home in the Yangtze River, China's famed White River Dolphin, or Baiji, is "likely extinct" according to a report in this month's edition of the journal Biology Letters. The determination was made half a year ago, after an expedition to find the graceful and intelligent dolphin (Lipotes vexillifer) was unsuccessful. This could be the first global extinction of megafauna—a creature larger than about 200 pounds (100 kilograms)—for more than 50 years, since the disappearance of the Caribbean monk seal, the fourth disappearance of an entire mammal family since 1500, and the very first dolphin to face human-driven extinction. It's estimated the baiji''s lived for 20 million years. "It's been here longer than the Andes Mountains have been on Earth," said marine biologist Barbara Taylor.
'All the stroboscopic lights and flares and mirrors and lasers and things. Constantly confusing information. After a day or two you'd become completely bewildered and disoriented and start to fall over the furniture.'
`Well, that's exactly what's happening, in fact [replied co-author Mark Carwardine]. The dolphins are continually being hit by boats or mangled in their propellers or tangled in fishermen's nets. A dolphin's echolocation is usually good enough for it to find a small ring on the sea bed, so things must be pretty serious if it can't tell that it's about to be brained by a boat.
`Then, of course, there's all the sewage, the chemical and industrial waste and artificial fertiliser that's being washed into the Yangtze, poisoning the water and poisoning the fish.'
`So,' I said, 'what do you do if you are either half-blind, or half-deaf, living in a discotheque with a stroboscopic light show, where the sewers are overflowing, the ceiling and the fans keep crashing on your head and the food is bad?'
'I think I'd complain to the management.'
Indeed, while some have pointed fingers at pollution and construction of dams -- the Yangtze is home to the world's largest -- mostly to blame are local fishing practices that sustain millions of people around the Yangtze but which involve harmful gill nets, rolling hooks or electrical stunning.
In a sense, this accidental extinction is scarier than hunting-related extinctions, as fishing and other human activities are much less obvious dangers. "We have to find a way to let small-time fishermen put food on their tables that doesn't involve putting gill nets in the water that decimate these species," Taylor said.
Even if there are some baiji still alive, the continued deterioration of the Yangtze region's ecosystem—home to roughly 10 percent of the world's human population—doesn't bode well for the baiji's chances of long-term survival. Conservationists are also trying to protect endangered cetaceans like the vaquita or Gulf of California porpoise (Phocoena sinus), of which 250 survive, and the Amazonian pink river dolphin, which fishermen are killing for use as bait. There are other threatened species in the Yangtze, including the Chinese sturgeon (which have been restocked in the polluted river) and another cetacean, the finless porpoise. To keep the porpoise from going where the baiji went, the researchers say "immediate and extreme" measures are needed.
Rest in peace, baiji.