Categorical Aperitif

After watching the Shuttle launch last night, I was catching up at Sam Smith's ever-informative Progressive Review when I ran across something that made me feel tremendously sad, and I'm not sure that I understand why:

After more than 20 million years on the planet, the Yangtze river dolphin is today officially declared extinct, the first species of cetacean (whale, dolphin or porpoise) to be driven from this planet by human activity.

An intensive six-week search by an international team of marine biologists involving two boats that ploughed up and down the world's busiest river last December failed to find a single specimen.

Today, the scientific report of that expedition, published in the peer-reviewed journal of the Royal Society, Biology Letters, confirms the dolphin known as the baiji or white-fin in Chinese and celebrated for its pale skin and distinctive long snout, has disappeared.

To blame for its demise is the increasing number of container ships that use the Yangtze, as well as the fishermen whose nets became an inadvertent hazard.

This is no ordinary extinction of the kind that occurs frequently in a world of millions of still-evolving species. The Yangtze freshwater dolphin was a remarkable creature that separated from all other species so many millions of years ago, and had become so distinct, that it qualified as a mammal family in its own right. It is the first large vertebrate to have become extinct for 50 years and only the fourth entire mammal family to disappear since the time of Columbus, when Europeans began their colonisation of the world.

Several other species are "just hanging on" in the Yangtze and could disappear within a few years unless action is taken now, Dr Turvey warned. They include the Chinese alligator, the finless porpoise and the Chinese paddlefish, which grows up to 7m long but has not been seen since 2003.

[...]

The object of last December's expedition was to rescue any baiji found and remove them to a 21km-long oxbow lake in the nature reserve of Tian'ezhou for an intensive breeding programme. Each of the two boats operated independently with scientists scanning the water with binoculars - dolphins have to surface to breathe - and listening with hyprophones for the distinctive whistles. Despite the technology, they found nothing.

"We used a very intensive survey technique. Both of the boats counted the same number of porpoises - we saw everything that was there. We didn't see a single dolphin," Dr Turvey said.

The cause of the freshwater dolphin's demise was instead all too plain to the investigators. It had become a victim of the world's most populous country's race to get richer. One tenth of the world's population live in the Yangtze river basin. During the expedition, scientists counted 19,830 ships on the 1,669km of the river they surveyed - one large freight vessel every 800m.

The Yangtze dolphin navigated by sonar - its eyes are useless in the murky water - but in a motorway jammed with container ships, coal barges and speed boats, its sonar was deafened and it ran a high risk of being hit or torn by propellers.

An even greater threat came from the nets and 1,000m lines of hooks used by fishermen.

Although they did not intend to catch dolphins, the creatures became entangled in the nets or lacerated by the bare hooks - almost half of all dead baiji found in the past few decades have died in this way. In addition, pollution had fouled their natural habitat and completion of the Three Gorges Dam worsened the decline in smaller fish on which the baiji fed.

"We didn't see a single dolphin." I'm not sure why, but that sentence makes me feel a profound sadness. It's only a single species, after all, and countless thousands before it have gone extinct, whether at the hand of evolution, catastrophe, or man. Hell, when I was playing in the beachside palmetto scrub as a kid, it's possible that I saw one of the last surviving Dusky Seaside Sparrows—not that I'd have known what I was looking at, or why it mattered. Maybe it was because, as I read the account of how the dolphin's mighty river home had become clogged with ships and hooks and noise and nets, I found myself wondering whether the baiji had a concept of Hell—and whether the remnants of their kind thought they were in it.

Some ironies are just cruel:

Mindful of the dolphin's crucial symbolic importance, and keen to replicate the success at breeding endangered species it had with giant pandas, the Chinese government set up a reserve in a lake in central Hubei province to look after baiji. But they were too late - there were no dolphins left to start an artificial propagation programme.

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