So long, and thanks for all the fish

Yangtze River Dolphin

If the Yangtze river dolphin isn’t quite extinct yet, it soon will be. Conservationist Mark Carwardine tells the tale of its last daysThe first time I went in search of the Yangtze river dolphin, or baiji, was in 1988 with Douglas Adams, author of ‘The Hitchhikers Guide to the Galaxy’, as part of a year spent travelling the world in search of endangered species for a book and radio series called ‘Last Chance to See’. We explored a small part of the Yangtze, which runs for 6380 kilometres through the heart of China.

We were overwhelmed by the dolphins phonomenally high profile in CHina. We drank Baiji beer and Baijicola, stayed in the Baiji Hotel and used Lipotes vexillifer toilet paper. We even came across Baiji weighing scales and Baiji fertiliser. It was the aquatic equivalent of the giant panda.

Unfortunately, though, we failed to see a single dolphin in the wild. We weren’t surprised – the Yangtze river is vast and the dolphins were notoriously hard to see, surfacing briefly without a splash.

Douglas and I did meet Qi-Qi (pronounced chee-chee), a beautiful bluish-grey dolphin with a long, narrow, slightly upturned beak, a low triangular dorsal fin, broad flippers and tiny eyes. Qi-Qi was just a year old when he was injured by fishing hooks in 1980 and taken into captivity to be nursed back to health. He was kept at the Institute of Hydrobiology in Wuhan for 22 years, where he taught scientists much about his disappearing species until his sad death on 14 July 2002. He reminded me of Martha, the last of the passenger pigeons, who died in Cincinnati Zoo in 1914.

I’ve been back several times since that first visit and, to my eternal regret, never did encounter a wild free Yangtze river dolphin. Now I never shall. The Yangtze river dolphin, Lipotes vexillifer, is the first cetacean to be driven to extinction by human activity.

Last month a Chinese man captured video footage of what might have been a lone baiji, boosting hopes that there might be a few survivors. Of course, that is a possibility, though the validity of the distant, poor-quality video has been questioned by experts. However, any hope of capturing a breeding pair has all but vanished, and the continued deterioration of the Yangtze ecosystem means that without human intervention the dolphins have no chance of survival. The species is functionally extinct, even if it is not actually extinct.

This is no ordinary extinction. We have lost large mammal species before, most recently the Caribbean monk seal, Monachus tropicalis, which was hunted to extinction in the 1950’s. The Yangtze river dolphin, however, was especially remarkable because it was the sole member of a distinct mammal family, the Lipotidae. It diverged from other cetaceans more than 20 million years ago, so its disappearance represents the end of a much longer branch of the evolutionary tree than most extinctions.

It’s a shocking tragedy. It’s also downright inexcusable. We had plenty of warning that the dolphin was in serious trouble – more than 20 years, no less – yet we failed to provide it with adequate protection. Accidental deaths due to fishing and shipping, over fishing, the rapid deterioration of the Yangtze river, an outrageous lack of funds, ineffective project management and incessant bickering between the Chinese authorities and western scientists sealed its fate a long time ago.

Even before it vanished, surprisingly little was known about the baiji. It wasn’t brought to the attention of western scientists until 1916, when a lone individual was killed by an American missionary’s son and taken back to the US. Another 40 years passed before scientists in China began to study the species.

An exclusively freshwater dolphin, unique to China, the Yangtze river dolphin once lived along a 1700-kilometre stretch of the middle and lower reaches of the Yangtze river, from the magnificent Three Gorges region all the way to the river mouth. It also lived in two vast lakes connected to the Yangtze, Dongting and Poyang, and, until the 1950s, in the Qiantang, a river a few hundred kilometres to the south of the Yangtze.

The baiji was active during the day, typically living in small groups of three or four individuals, and apparently resting at night in areas where the current was slow. It fed mainly on fish, using its long beak to probe into the muddy riverbed around water confluences and sandbars with large eddies. It was a slow breeder, the females giving birth to a single calf once every two years.

Yangtze river dolphins had little need to see in the turbid waters of their riverine home, where viability can drop to about 12 centimetres in late summer. They could distinguish objects placed on the surface, so their eyes were functional – but only just. Instead, they used a highly developed sense of echolocatio, like other dolphins, to find their food and to navigate.

The species is mentioned in Chinese literature dating back 2200 years and Guo Pu (AD 276-324), a scholar of the Jin dynasty, described the river as “teeming” with dolphins. Revered as the “Goddess of the Yangtze”, according to legend the baiji was the reincarnation of a princess who had refused to marry a man she did not love and was drowned by her father for shaming the family. Fishermen believed its appearance was a friendly warning of an impending storm and that anyone who hurt one would come to a tragic end. Until recently, this superstition helped protect the animal.

All that changed during the Great Leap Forward in the late 1950s. The dolphin’s respected status was suddenly denounced and, instead of being revered, it was hunted for its flesh and skin. A factory was even established to make handbags and gloves out of dolphin skin, though it did not last long as the animals quickly became scarce.

Even after the hunting ended, fishing – the main killer of porpoises, dolphins and whales worldwide – took a heavy toll. The dolphins liked to feed exactly where fishermen set their gill nets and fyke nets, resulting in many being caught accidentally, and drowned. At least half of all known dolphin deaths in the 1970s and 1980s were caused by rolling hooks – lines of hooks up to a kilometre long – and other fishing gear. Electro fishing – applying a current to water – accounted for 40 per cent of deaths during the 1990s. Rolling hooks and electrofishing are illegal, but still common.

Blinded and deafened

Indeed, the dolphin couldn’t have picked a worse place to live. The Yangtze river basin is home to an astonishing tenth of the human population. Accessible to ocean-going vessels up to 1000 kilometres from the sea, the Yangtze is one of the busiest rivers in the world. A 2006 survey counted 19,830 large ships – more than one per 100 metres of river surveyed – and 1175 +fishing vessels. Not only did collisions with boats and propellers kill many dolphins, the roar of the ships’ engines both ‘blinded’ and deafened them, making echolocation and communication with other dolphins near impossible.

There was also less food for the dolphins. Catches have plummeted to a fifth of what they were in the 1950s due to over fishing and other problems. With industrialisation and the spread of modern agricultural practices, ever more pollution pours into the river each year. The natural banks of the river have been dredged and reinforced with concrete along much of its length to prevent flooding, yet flood plains are crucial for the reproduction of many riverine fishes.

Then there is the Three Gorges Dam, the largest hydroelectric dam ever built, which has dramatically changed water levels, stratification, currents and sandbanks. Smaller dams along other parts of the river fragmented dolphin popualtions, blocked migration and made important feeding and breeding areas inaccessible.

From as many as 5000 or 6000 dolphins in the 1950s, the population shrank to 400 by around 1980, 200 to 300 by 1985, fewer than 100 in 1990 and just 13 by 1998. The warning signs don’t get more obvious than that. The last authenticated sightings were of a stranded pregnant female found in 2001 and a live animal photographed in 2002. There have also been four unconfirmed reports since then, including the indistinct video filmed in August. And that’s it. There hasn’t been a confirmed sighting for years.

The last organised search was an intensive six-week expedition for 6 November to 13 December 2006 (Biology Letters, DOI:10.1098/rsbl.2007.0292). The survey, by researchers from China, Japan, the US, Switzerland and the UK, used two vessels operating independantly. Covering the entire historical range of the species, they twice scanned the 1669 kilometres of the river with binoculars and listened for telltale squeaks and whistles with high-tech hydrophones. All to no avail.

Importantly, both vessels counted the same number – around 400 – of Yangtze finless porpoises (Neophocaena phocaenoides asiaaeorientalis), a freshwater subspecies unique to the river. This suggests that the scientists really did see everything there was to see, so their failure to find any evidence of Yangtze river dolphins strongly implies that there were none to find. This week the World Conservation Union (IUCN) will change the species’ status from “critically endangered” to “critically endangered (possibly extinct)”.

The original aim of the survey was not to sound the death knell but to rescue any surviving dolphins and translocate them from the river to a 21-kilometre long, 2 kilometre wide oxbow lake in Hubei province, called Tian’ezhou. It has healthy fish stocks and is already home to a small popualtion of about 25 finless porpoises, introduced in 1990. Conditions would almost certainly have suited the dolphins, and the plan was to establish an intensive breeding programme. Ecotourism could have generated much-needed revenue for its upkeep.

It was a good plan, but it was 20 years too late. The idea of moving individuals to a safe reserve was first mooted in the mid-1980s and had been consistently advocated ever since. Douglas Adams and I went to visit one potential reserve, near Tongling, during our visit in 1988. In the 1990s, six capture attempts were made, but with little success. A female was finally caught and relocated to Tian’ezhou in 1995, but she was found dead seven months later, entangled in the escape-prevention nets at the outlet of the reserve.

All along, efforts were hampered by disputes among conservationists, scientists and the Chinese authorities about whether this was the best approach. Admittedly, it would have been an expensive strategy. it required boats to capture the dolphins, helicopters to transfer them, holding pens and veterinary staff to care for them before they could be released into the semi-natural reserve, a proper inventory – and management – of fish stocks, and round-the-clock protection. But the dolphins should have been a conservation priority, so why wasn’t the money forthcoming?

If only everyone had agreed on a recovery programme 20 years ago, when establishing a semi-natural population was still a viable proposition, the outcome could have been very different. Even in the shadow of China’s economic boom and burgeoning population, the baiji could have been saved. Ultimately, it was as much a victim of incompetence, indecision and apathy as it was of environmental deterioration.

In response to the dolphin’s obvious decline, the Chinese government did give it official protection in 1975, making the deliberate catching or killing of a dolphin a punishable offence. It also declared the animal a “national treasure”. In 1992, it set aside five protected areas along roughly 350 kilometres of the Yangtze river and established five baiji protection stations, each with two observers and a small motor boatm to conduct daily patrols, make observations and investigate illegal fishing. In 2001 fishing was banned in parts of the river between April 1 and 30 June.

It all looked good on paper, but it was too little too late and lacked the resources and coordination to work. The patrol boats were old and too slow to catch illegal fishermen, for example, and the laws were poorly enforced.

Meanwhile, international conservation organisations kept calling for action. While some did make a positive contribution to conservation efforts, many didn’t. Others withdrew their support because of the enormitiy of the challenge and the dwindling sense of optimism for the baiji’s chance of survival. It turns my stomach to read their official statements expressing ‘shock’ and ‘dismay’ at the loss of the species, when they were too slow, too cautious and too downright inept to do anything constructive. Despite all their workshops, conventions and meetings on the Yangtze river dolphin, conservation organisations must shoulder a large part of the blame for its demise.

Will we learn any lessons from the loss of the baiji? It’s an important question, because there are other endangered species in the river that could disappear soon unless immediate action is taken. These include the Asian softshell turtle, Chinese alligator, and the smooth-coated otter, as well as the fast-declining Yangtze finless porpoise.

In other parts of the world, we barely have time to mourn the baiji before worrying about two of its closest relatives: the Indus river dolphin, with around 1000 remaining in Pakistan; and the Ganges river dolphin, of which a few thousand remain in western India, Bangladesh, Nepal and Bhutan. They face remarkably similar threats to their vanished Chinese relative, and their fate could be exactly the same.

How loud, and for how long, do the alarm bells have to ring before we take decisive action? If we can’t save an appealing and charismatic dolphin – one that has lived on Earth for more than 20 million years – what can we save. Mark Carwardine New Scientist #2621

That last paragraph rings so true.

How loud and for how long do the alarm bells have to ring……?

And really, in this depressing ecological age, what can we save?

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: