It is extremely sad to learn that the Yangtzee River Dolphin, also called the Baiji, is now extinct (one of my favorite creatures). Scientists believe that even if there are a scattered few around, there are not enough to reproduce and perpetuate the species. The long, slow death of the Baiji was caused by overfishing, construction of the Three Gorges Dam and other changes in the vicinity of the Yangtze River.
The construction of the Three Gorges Dam is an unprecedented behemoth. The hydroelectric dam is the largest in the world as of 2007; more than five times the size of the Hoover dam. It will in turn be a cataclysmic destructive force upon the cultures that lived on the river for thousands of years and the species that have lived longer than that in the river.
Among our losses is the ability to study the Baiji’s extraordinary use of sound. Largely blind, this dolphin is capable of using sound to stun and even kill its prey. Its sonar easily out-rivals that of the military with its precision echolocation under extremely turbid conditions. The freshwater dolphin is known for its ability to produce three dimensional representations of objects in its mind: it is capable of seeing through a box and detecting the shape and type of metal hidden inside. It’s teeth are adapted to act as an array of receivers that vibrate in response to pressure from sound waves. I speak in present tense because I can’t yet accept it’s loss. This dolphin could have been used to better understand sound perception.
“We have yet to take full responsibility in our role as guardians of the planet”
Dr Sam Turvey, Zoological Society of London
On a side note: Douglas “Hitchhikers Guide to the Galaxy” Adams wrote about the Baiji Dolphin in his recent environmental book “Last Chance To See”:
Well, it’s worse than that, isn’t it? Mark said. ‘Dolphins rely on sound to see with.’
‘All right, so it would be like a deaf man living in a discotheque.’
‘Why?’
‘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. 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.’
‘They can’t.’
more:
Read a longer excerpt here (Link)
Listen to the Baiji whistle (like Brian Eno music)
