A research expedition underway this week on China's mighty but polluted and traffic-choked Yangtze river is racing against time to save one of the earth's rarest dolphins.
The baiji, believed to be among the world's oldest fresh-water mammals, may already be extinct but an international team of scientists and ecologists are hoping against formidable odds that the dolphin has survived.
"We are just hoping the baiji are still here," Brent Stewart, a research biologist from Hubbs-Seaworld Research Institute in San Diego, said aboard the Kekao One, one of the expedition's ships.
Expectations among the experts from China, Japan, Switzerland and the US that the baiji has overcome China's relentless environmental degradation are tempered by gritty reality.
Massive pollution from factories along the banks of the world's third longest river dump brown, foul smelling effluent into the water.
Fisherman, their silhouettes dotting the river's turbid waters, cast lethal kilometer-long nets that result in severe over fishing of the baiji's food source.
The rolling hook fishing nets also inadvertently trap the baiji, while illegal dynamite fishing blows them to bits. Electrofishing stuns them just long enough so they can drown.
Meanwhile, giant barges weighed down with coal, oil, gas and minerals -- among the many key resources China consumes to power its booming economy -- crowd the baiji out of its river home.
August Pfluger, co-expedition chief and head of Swiss-based baiji.org, an environmental group dedicated to saving whales and dolphins, put the baiji's chance of survival at around 5 percent.
China's unprecedented industrialization over the past 30 years has so damaged the Yangtze's ecology that today fewer than 50 baiji are believed to survive, according to researchers on the expedition.
Wang Ding, head of China's Institute of Hydrobiology and one of the world's foremost experts on Yangtze marine life, said the fate of the baiji highlighted China's willingness to sacrifice the environment for economic progress.
"China used to be poor and so it always focused on economic development, while society just didn't care about nature," Wang said.
"Now society has started to realize what has happened. Maybe it is too late but we have to do something otherwise it will be gone for sure," he said.
The objective of the six-week expedition is to find, count and observe the baiji, then capture them and put them in a safer home such as an aquatic reserve.
Aboard the two ships, scientists armed with high-tech optical and acoustic equipment, as well as a group of trained observers, will have scoured 1,750km of the Yangtze when their voyage from Wuhan to Shanghai is complete.
But even the high-tech efforts to monitor the dolphins are being hampered by the frantic economic activity.
The incessant roar of ships' engines drowns out the eerie, melancholic high-pitched whine of the baiji.
"Ships' engine noise sounds like the baiji, so you get noise contamination that can result in missing 50 percent of the sounds," said Tomonari Akamatsu, an underwater bio-acoustics expert from Japan's National Research Institute of Fisheries Engineering.
On a nine-day trip in March researchers failed to find a single baiji, which relies on its highly developed sonar system instead of its eyes.
But with its navigational system impaired by the shipping activity the baiji has become the marine equivalent of road kill -- an animal run over and butchered beneath boat propellers.