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Post by dantheman9758 on Mar 30, 2007 12:07:35 GMT
could the dolphin, thousands of years ago, have split into two or more groups and there for be found ina deep ocean valley or something? Don't forget dolphins are mammals and need to breathe, it would be extremely inefficient and impossible for a tiny dolphin like animal that needs to breathe air to live at depths of 1 - 2 miles. I don't think even a sperm whale could do that, as they need to spend atleast 10 minutes on the surface making changes to their blood pressure and oxygenating their blood before they make their deep dives. -- And they only go that deep to feed, they do most of their migrating and "socializing" near the surface of the water... So again a Dolphin is a mammal, and it needs to breathe! so i doubt any secret population of ancient Cetacean will be found swimming along in a deep ocean valley (unless its a sperm whale)
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Post by sebbe67 on Jun 11, 2007 6:08:25 GMT
The Qiantang River dolphin?The Qiantang River is a large river in eastern China that travels through Jiangxi and Zhejiang provinces. Although several hundred miles south of the Yangtze, the Qiantang also contained a population of Yangtze River dolphins or baiji (Lipotes vexillifer) well into the twentieth century. It is not as big as the Yangtze, but is still a large river: it has a total length of 484 km, a drainage basin of 42,000 km2, and an average annual flow of 40.4 billion m3. In the areas where baiji were found, the width of the river was between 500 and 1200 metres. Since the river is situated in a similar climate zone to the Yangtze, it is not surprising that it was able to support baiji, although how they got there in the first place is open to speculation. Very little information is available about the former occurrence of baiji in the Qiantang River. During a flood in the 1950s there were reports of seeing about ten baiji in the river between the towns of Tonglu and Fuyang, about 320 kilometres from the river mouth. One of these individuals was killed and collected, and is now on display at the Zhejiang Natural History Museum in Hangzhou – a picture of this specimen can be seen here. This report strongly suggests that these baiji were not just animals occasionally straying from the main population in the Yangtze, but instead represented a resident population. It is not clear what the total baiji population was in the river. However, given that marine biology in China was in its infancy in the 1950s and that no scientific research was carried out during the 1960s because of the Cultural Revolution, the fact that at least ten individuals were reported strongly suggests that there were many more in the river at that time. Nobody knows exactly why baiji are no longer seen in the Qiantang River. Human impacts along the river are very similar to those in the Yangtze, and the reasons for the disappearance of the species are probably the same in both rivers: destructive fishing practices, dam construction and boat traffic. Of these factors, dam construction is often considered to be the most likely reason, as a large dam was built at Xinanjiang on the Qiantang in the late 1950s, and this coincides with the end of reported sightings of baiji in the river. However, none of these theories have been thoroughly studied, and remain very speculative. It is still (remotely) possible that there are still some baiji hiding out in some remote bend of the Qiantang, as the river has not been surveyed for cetaceans for many years. How did baiji originally get into the Qiantang River? It is possible that they could have migrated from the Yangtze to the Qiantang when the mouths of the two rivers were closer to each other than they are today. During recorded history, both river mouths have changed location drastically due to the build-up of silt. It is not hard to imagine that in the 20 million year history of the baiji, at one point the two mouths were located close enough for them to easily migrate from one river to the other. However, it is also possible that the Qiantang may have been originally connected to the Yangtze. The Qiantang River apparently still contains finless porpoises, which are occasionally seen in the river. The last time they were seen as far upstream as Tonglu was in the 1990s, though they are often seen by the river mouth in Hangzhou. However these finless porpoise are not the same subspecies as the one endemic to the Yangtze (Neophocaena phocaenoides asiaeorientalis), but instead represent the subspecies found along the eastern coast of China and in the Sea of Japan (Neophocaena phocaenoides sunameri). The fate of the Qiantang River’s finless porpoises remains uncertain, and continued development and industrialization along the river may mean that they will share the same fate as the river’s former population of baiji. www.edgeofexistence.org/blog/?p=59
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Post by another specialist on Jun 19, 2007 8:14:15 GMT
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Post by Melanie on Aug 7, 2007 22:37:09 GMT
CHINA-DOLPHIN/EXTINCTRare Yangtze River Dolphin Probably Extinct-StudyThe long-threatened Yangtze River dolphin in China is probably extinct, according to an international team of researchers. Reuters The long-threatened Yangtze River dolphin in China is probably extinct, according to an international team of researchers who said this would mark the first whale or dolphin to be wiped out due to human activity. The freshwater dolphin, or baiji, was last spotted several years ago and an intensive six-week search in late 2006 failed to find any evidence that one of the rarest species on earth survives, said Samuel Turvey, a conservation biologist, at the Zoological Society of London, who took part in the search.
He said the dolphin's demise -- which resulted from overfishing, pollution and lack of intervention -- might serve as a cautionary tale and should spur governments and scientists to act to save other species verging on extinction.
"Ours is the first scientific study which didn't find any," he said in a telephone interview. "Even if there are a few left we can't find them and we can't do anything to stop their extinction."
The team, which published its findings in the Journal of the Royal Society Biology Letters on Wednesday, included researchers from the United States, Britain, Japan and China. The survey was also authorized by the Chinese government, Turvey said.
The last confirmed baiji sighting was 2002, although there have been a handful of unconfirmed sightings since then. The last baiji in captivity died in 2002, Turvey said.
During the six-week search, the team carried out both visual and acoustic surveys and used two boats to twice cover the dolphin's 1,669 kilometre range stretching from the city of Yichang just downstream from the Three Gorges dam to Shanghai.
The last such survey conducted from 1997 to 1999 turned up 13 of the mammals, but Turvey said fishing, pollution and boat traffic in the busy river, home to about 10 percent of the world's population, has likely meant the baiji's end.
"We covered the whole range of the dolphin twice," Turvey said. "It is difficult to see how we could miss any animals."
The dolphins will now be classified as critically endangered and possibly extinct but Turvey said there is little chance any remaining baiji are alive.
Researchers have known for years about the dolphin's precarious situation but indecision about how best to save the species meant little was actually done, he added.
This underscores the need to act quickly to prevent the extinction of other similar shallow-water aquatic mammals like the vaquita found in the Sea of Cortez and the Yangtze finless porpoise, Turvey said.
"One really needs to learn from this to make sure future conservation efforts are more dynamic," he said. "There has always been so much focus on 'save the whale' and 'prevent whaling' that it has led to these range-restricted shallow cetaceans slipping through the crack."
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Post by Melanie on Aug 7, 2007 22:50:59 GMT
Baiji declared officially extinct!
River dolphin is wiped outMark Henderson, Science Editor A species of dolphin has been driven to extinction by human activity for the first time, scientists confirmed yesterday.
A six-week survey of the entire habitat range of the Yangtze river dolphin, or baiji, which is found only in the great Chinese river system, found no evidence for its survival. The dolphin is the first large vertebrate to become extinct for more than 50 years. It is also the only species of cetacean � the order of mammals that includes whales, dolphins and porpoises � to have died out because of human influence.
Its disappearance has been blamed on fishing nets that inadvertently trap and drown the dolphins, and on degradation of its habitat.
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Post by Melanie on Aug 7, 2007 22:56:27 GMT
BEIJING: When the last white-fin dolphin, or baiji, died, so too did a piece of China's soul.
This peaceful mammal was known as the Goddess of the Yangtze and for millions of years, she ruled the waters of China's longest river.
But breakneck development, over-fishing and a massive increase in shipping traffic led to the animal's extinction within a few short years.
The almost-blind, long beaked animal, one of the oldest mammals on the planet at around 20 million years old, now officially becomes the first big aquatic mammal to disappear since hunters killed off the Caribbean monk seal in the 1950s.
Measuring up to 8'2" in length, the baiji is, or at least was, a relative of other freshwater dolphins found in the Mekong, Indus, Ganges and Amazon rivers.
Local legend has it that the baiji is the reincarnation of a princess who refused to marry a man she did not love and was drowned by her father for shaming the family.
The baiji had no natural predators, except for man.
Advertisement AdvertisementThe white-fin dolphin shared its habitat on the rushing waters of the Yangtze with huge river cruise ships, tugboats and fishing boats.
Too often, the almost-blind beasts crashed into ship's propellers, as fishing boats played havoc with the sonar systems they used to chart their course along the river.
Fishermen using explosives or catching them in their nets illegally also devastated the baiji population.
The lack of oxygen in the Yangtze due to breakneck industrialisation contributed to the mammal's demise.
Despite a growing list of adversities, there were still 400 white-fin dolphins or lipotes vexillifer alive during the 1980's, but that number dropped significantly, and alarmingly, to less than 150 in the last decade.
A survey in 1997 listed just 13 sightings, with the last confirmed sighting in 2004.
The final baiji in captivity, Qi Qi, died in2002.
It was declared "functionally extinct" after an expedition last year.
To understand how devastating the extinction of the white-fin dolphin, you need to understand the importance of the Yangtze river to the Chinese national psyche.
The Chinese call it simply chang jiang, or long river, and as well as having a huge symbolic value, it is an essential shipping route, is economically vital to a whole region and also waters one of the most densely populated areas on Earth.
The Yangtze runs 6,300 kilometres through nine provinces from western China's Qinghai-Tibet Plateau to the East China Sea.
Yangtze is mostly a name used by foreigners to describe it.
Recent reports have shown that nearly 30 per cent of the river's major tributaries, including the Minjiang, Tuojiang, Xiangjiang and Huangpu rivers, are now seriously polluted.
Mindful of the white-fin dolphin's crucial symbolic importance, and keen to replicate its success at breeding endangered species that it had with giant pandas, the Chinese government set up a reserve in a lake in central Hubei province to look after baiji in capitivity.
But they were too late - there were no dolphins left to start an artificial propagation programme.
The extinction of the white-fin dolphin is not the end of the story.
China's other indigenous cetaceans are in trouble, facing threats from pollution and expansion.
The expedition that searched for the baiji also exposed the threat to other species.
They spotted about 300 of another endangered freshwater mammal, the Yangtze finless porpoise, far fewer than expected.
The mammal lived only in the Yangtze and was described by marine biologists as a living fossil because it remained essentially unchanged over the 20 million years since it first entered the river.
The river regularly bursts its banks and floods the surrounding areas with spectacular results - one of the main reasons for building the Three Gorges Dam, the world's largest water storage facility, was to regulate the river's level.
Advertisement AdvertisementThe flooding is liable to get worse, according to some experts.
And now there is no longer a Goddess of the River to bring good luck to the currents of the Yangtze.
- INDEPENDENT
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Post by another specialist on Aug 8, 2007 4:57:28 GMT
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Post by sebbe67 on Aug 8, 2007 11:29:52 GMT
There is not many photos in this thread so here is some www.edgeofexistence.org/home.aspThere is a slideshow on this website with photos, including photos taken from the recent search for this exclusive dolphin.
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Post by Melanie on Aug 8, 2007 17:36:33 GMT
The Yangtze River dolphin or baiji (Lipotes vexillifer), an obligate freshwater odontocete known only from the middle-lower Yangtze River system and neighbouring Qiantang River in eastern China, has long been recognized as one of the world's rarest and most threatened mammal species. The status of the baiji has not been investigated since the late 1990s, when the surviving population was estimated to be as low as 13 individuals. An intensive six-week multi-vessel visual and acoustic survey carried out in November–December 2006, covering the entire historical range of the baiji in the main Yangtze channel, failed to find any evidence that the species survives. We are forced to conclude that the baiji is now likely to be extinct, probably due to unsustainable by-catch in local fisheries. This represents the first global extinction of a large vertebrate for over 50 years, only the fourth disappearance of an entire mammal family since AD 1500, and the first cetacean species to be driven to extinction by human activity. Immediate and extreme measures may be necessary to prevent the extinction of other endangered cetaceans, including the sympatric Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis). www.journals.royalsoc.ac.uk/content/15782wq480207749/
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Post by sebbe67 on Aug 10, 2007 12:54:46 GMT
Baiji declared extinct8th August, 2007 After more than 20 million years on the planet it looks as if we have now lost the Yangtze River dolphin or baiji forever. The question scientists are now asking is could this tragedy have been prevented? The failure to find any sign of the baiji (Lipotes vexillifer) during last year’s Yangtze River survey has forced Sam and fellow survey participants to concede that the species may now be extinct. If true, this makes the baiji is the first large vertebrate to disappear from the planet for more than fifty years, and the only species of cetacean (whale, dolphin or porpoise) to be driven to extinction by human activity. The scientific paper detailing what went wrong for the baiji is published today in the Royal Society’s journal Biology Letters. The paper also describes the November-December 2006 survey, during which optimistic conservation biologists hoped to capture the few remaining baiji and translocate them to a protected part of the river system. The intensive six week survey covered the entire historical range of the species in the main channel of the Yangtze River in eastern China yet failed to find a single individual. It is believed that the main factor responsible for the disappearance of the baiji was the accidental death of large numbers of dolphins in fishing gear, rather than active persecution. However, what saddens the EDGE team the most is that the baiji could still be here today if only the conservation community had acted sooner. Thirty years ago the population stood at 400, and during the 1980s and 90s both Chinese and international scientists consistently recommended the translocation of baiji from the river to a safer environment. However, despite these repeated and specific recommendations, nearly all conservation work was limited to a series of surveys conducted from the late 1970s onwards. Although they provided valuable data on the baiji’s decline, in the end, additional surveys were not a solution to the problem and they failed to save the species from extinction. We will never know for sure if we could have saved the baiji, but at least we could have tried. Now, all that is left is hope. It is possible that a few dolphins may have been mised by the survey team. While there’s a chance that baiji are still around we need to act quickly. We are extremely grateful to everyone who has donated to the baiji project over the past 7 months, but we urgently need more funds to allow Sam to return to China and carry out a wide-range series of interviews with fishermen along the Yangtze. This research has two main objectives: 1) to determine how and why conservation efforts failed in this case, and 2) to compile as much information as possible on the life and death of the baiji while that knowledge still exists in the living memory of fishermen along the river. The river survey will probably also provide the last, best chance to document any possible surviving baiji. See here for more information. Sam recently commented to the media, “The loss of such a unique and charismatic species is a shocking tragedy. The Yangtze River dolphin was a remarkable mammal that separated from all other species over twenty million years ago. This extinction represents the disappearance of a complete branch of the evolutionary tree of life and emphasises that we have yet to take full responsibility in our role as guardians of the planet.” www.edgeofexistence.org/edgeblog/?p=93
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Post by Melanie on Aug 10, 2007 15:40:56 GMT
How stupid are scientists? The most people on this planet are neither interested to save the nature nor to prevent species from extinction.
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Post by another specialist on Aug 13, 2007 7:42:30 GMT
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Post by another specialist on Aug 13, 2007 7:48:33 GMT
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Atlas
Full Member
Posts: 76
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Post by Atlas on Aug 14, 2007 0:48:07 GMT
"How stupid are scientists? The most people on this planet are neither interested to save the nature nor to prevent species from extinction"
If that is true many more wildlife educators are needed. I suppose that the problem with that is that the only people that listen to them are already environmentalists....
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Post by Melanie on Aug 14, 2007 13:53:14 GMT
Of course we need much more wildlife educators but in particular in countries were the species are on the brink of extinction, like China or Indonesia. The problem is that many local governments don't want to hear the warnings of the educators, they only think how they can gain their economy without thinking that humans NEED a healthy nature to survive. "How stupid are scientists? The most people on this planet are neither interested to save the nature nor to prevent species from extinction" If that is true many more wildlife educators are needed. I suppose that the problem with that is that the only people that listen to them are already environmentalists....
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Atlas
Full Member
Posts: 76
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Post by Atlas on Aug 14, 2007 15:27:41 GMT
Corruption and greed are nearly always the cause of damage...
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Post by another specialist on Aug 26, 2007 15:46:24 GMT
We will never learn I guess what damage we can cause and have caused to the world we live in.
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Post by Melanie on Aug 29, 2007 18:34:01 GMT
A CHINESE man has videotaped a large white animal swimming in the Yangtze river, which experts say is a dolphin species unique to China and feared extinct, the official Xinhua agency reported.
The last confirmed sighting of the long-beaked, nearly blind baiji was in 2004.
After an international team failed to find a single dolphin on a six-week expedition last year the species was classified as critically endangered and possibly extinct.
But the video from central Anhui province may renew slender hopes for the survival of the creatures also known as white-flag dolphins and traditionally considered a deity by local people.
“I never saw such a big thing in the water before, so I filmed it,” dolphin-spotter Zeng Yujiang told Xinhua.
“It was about 1000m away and jumped out of water several times.”
Wang Kexiong, of the Institute of Hydrobiology of the Chinese Academy of Sciences, said experts at the institute had confirmed the footage was of a baiji.
The report did not say if there were any plans to try and locate the dolphin again, or try and protect it from the river hazards - ranging from pollution and aggressive fishing to heavy shipping traffic - that originally decimated the species.
In the late 1970s, scientists believed several hundred baiji were still alive, but by 1997 a survey listed just 13 sightings.
Found only in the Yangtze river, it is related to freshwater species found in the Mekong, Indus, Ganges and Amazon rivers.
The Government has set up a reserve in a lake in central Hubei province but failed to find any baiji to put in it.
The last captive dolphin, Qi Qi, died in 2002.
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Post by another specialist on Aug 29, 2007 21:06:00 GMT
So there may still be hope of it surviving. Fingers crossed.
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Post by thomassn on Sept 1, 2007 14:27:17 GMT
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