Baiji dolphin, R.I.P.

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China's white dolphin called extinct after 20 million years:

An expedition searching for a rare Yangtze River dolphin ended Wednesday without a single sighting and with the team's leader saying one of the world's oldest species was effectively extinct.

The white dolphin known as baiji, shy and nearly blind, dates back some 20 million years. Its disappearance is believed to be the first time in a half-century, since hunting killed off the Caribbean monk seal, that a large aquatic mammal has been driven to extinction.

A few baiji may still exist in their native Yangtze habitat in eastern China but not in sufficient numbers to breed and ward off extinction, said August Pfluger, the Swiss co-leader of the joint Chinese-foreign expedition.

Lipotes vexillifer, despite living in a highly trafficked area is very poorly understood. It hasn't been possible to maintain captive populations, and poor underwater visibility makes studies in the wild difficult. The construction of the Three Gorges Dam, along with fishing and heavier boat traffic, has driven population levels ever lower. This survey confirms what has long been expected – that this species cannot persist.

The genus name Lipotes means left behind. It is isolated in a unique habitat, and even without hunting pressure or active trade in the remains of dolphins, they are on the verge of extinction. The forces driving them to the limits also apply to a range of fish and other plants and animals that live in the Yangtze and in other rivers around the world.

Nothing hunts the baiji, even local human populations have long protected the species (though accidental deaths do happen, and the fat from killed dolphins is treated as medicinal). The dolphins are basically blind, and navigate the murky waters almost exclusively by echolocation. More traffic on the river, and more motorized traffic, has increasingly limited their ability to hunt and navigate.

On top of that, dams have changed river patterns and altered population dynamics of fish and the food the fish require. Subtle changes in the ecosystem up and down the river have been acting to drive the dolphins into danger. Reversing these changes is probably impossible, certainly impractical.

The other problem the baiji dolphin faces is even more difficult to overcome.

A dolphin lives at least 24 years (one wild dolphin was captured and accurately assessed at that age), and becomes reproductively active at 3-8 years. Females give birth to a single offspring once every couple years.

A single female could, in principle, have as many as 10 offspring in a lifetime then, though fewer is more likely. Figure in infant mortality, failures to reproduce in famine years, and other stresses, and the number of offspring reaching adulthood will get smaller. Any increase in mortality, or anything that reduces fertility, will endanger an organism that has evolved a life history that favors low birth rates. They will bounce back more slowly from any bad period, and extended bad times can drive them right to extinction.

This scenario is the same as most of the extinctions under way right now. Species are being pushed to the brink not by hunting, but by habitat degradation that affects whole swaths of life. I know it's politically infeasible, but this is exactly why we really do need an endangered habitats act.

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Sounds like this species, after 20 million years, reached an evolutionary dead end. It couldn't adapte to a changing environment. Natural selection can be a bitch sometimes.

In 2004 I took a two week long boat trip up the Yangtze. Of course, no one saw a baiji dolphin, and we were told not to expect to see any because there hadn't been any sightings in many years.

The lower reaches of the Yangtze are opaque, much more so than the Mississippi, not from pollution but from sediment. My understanding was that the baiji dolphin pretty much inhabited the lower reaches exclusively, i.e. the recent Three Gorges Dam, or the older Yangtze dam nearby were outside of their habitat.

The lack of highways through central China means that the river is still the primary means of transport, and the lower reaches of the river are filled with diesal powered barges.

Because of the opacity of the water, it was hard to tell how polluted it was. However, swimming was not recommended. The air was thick with the acrid order or sulfer dioxide. Even in the less developed areas above the dams the air wasn't clear.

While I would like to think that the Baiji dolphin is not extinct, it had adapted to a fairly restricted habitat that has turned out to be one of the more important arteries of transport in China.

Not that I'm an expert on any of this, these are just some observations from my trip. The other odd thing we noticed was the almost complete lack of birds.

I think it's a little flip to say that this species (or the many others going extinct right now) "reached an evolutionary dead end." The environment didn't just happen to change, we changed it in deliberate ways, making this artificial selection. My view is that since we caused these extinctions and near-extinctions, we are responsible for deciding if they are what we want.

I refrained from commenting on emawkc's earlier comment because he was either being flippant or unconscionably inhumane. I prefered to believe the former.

However, on consideration, an attitude like this does remind me of another thought I've been entertaining recently. The thought is still nascent, but it is a reflection on how certain opinions are really a type of panglossianism.

Some people appear to trust non-conscious forces as being responsible for various conditions found in the world. For example, emawkc professes to explain the probable extinction of the Baiji by claiming natural selection is responsible. I've read, and heard, other people claim that the 'invisible hand' of the free-market will create a utopia.

The trouble with both these views is that they suggest that humanity cannot use reason to upset what appears to be an inevitable outcome.

Humanity has very likely altered the habitat of the Baiji to the point where the Baiji cannot survive. There are many reasons humanity altered this ecosystem, your opinions on the value of these reasons may vary. However, the alteration was not inevitable. Restoring the ecosystem is not impossible (although it may be too late for the Baiji).

Restoring the habitat requires that humanity identify the causes of the damage and remove them. Humanity needs to identify how the original ecosystem operated and replace the missing parts. These activites require the use of our reason as well as our will.

Yet an attitude like emawkc's is a request to avoid thinking. Instead, the outcome is fore-ordained by the forces which shape the economic and social face of China. Reason can explain the non-conscious forces which caused this tragedy, but reason cannot control these forces. There is no need to use our reason to explain how the habitat was damaged or how to fix it because this is the best of all possible worlds. The 'invisible hand' of market forces cannot be managed because we will interfere with the best of all possible worlds that it promises.

These are appeals to avoid bearing responsibility for our actions. To avoid thinking rationally about what we do.

Mind you, I'm still hoping that emawkc was simply being flippant.

On that note, it's time to go pick up my half-barrel of beer. ;)

Whether humans are "part of nature" is a tricky question, best answered "yes and no." The "yes" argument is fairly obvious so I'll leave it as an exercise for the reader.

The "no" is trickier and gets us to interesting issues. I want to emphasize first that "nature" is not a scientific concept, dividing natural from artificial is a fundamentally philosophical question.

I would argue that the ability to conceive of nature as a discrete reification of some aspect of the universe is an act only possible of a consciousness that is not entirely part of nature. The ability to consciously and intentionally manipulate nature and natural phenomena would then be a hallmark of artificiality. Beavers manipulate the natural world, but since we have no basis for thinking that they conceive of their actions as changing something about "nature," a beaver dam isn't artificial.

Along with the ability to recognize how we are changing the natural world comes a responsibility to be consider our actions. This is true however you draw the line between natural and nonnatural. What happened to the baiji dolphins didn't just happen, we made it happen. With that action, we take responsibility for the consequences.

Thank you Josh and Flex, for your eloquent and articulate responses to the remarks of an ass-head.

Comments like those made by emwack drive me crazy. I remember getting upset at my brother in law (Who is a science teacher) when I was lamenting the potential extintion of the siberian tiger. His attitude was the same as emwack's, "yeah well, extinction happens". Sure, humans are a part of nature, I suppose in a round-about way you could argue that human distruction of habitat is a natural force at work. But unlike other forces of nature, human beings have a conscience. We know perfectly well that when we destroy a habitat we'll seriously affect the the organisms living within it. I have no problem with hunting as long as it carefully regulated but I have a feeling that if certain restrictions weren't imposed on, say whaling nations, they'd happily hunt every whale in the ocean to extinction. In another couple of hundred years the planet is going to be occupied by nothing more complex than 20 billion humans and a lot of rats and cockroaches.