These dolphins have had legal protection in China since 1975 and it is unlikely that they are still being killed deliberately for meat or for their blubber, which was once considered to be of medicinal value.
The majority of deaths are caused inadvertently. Some dolphins die after becoming impaled on 'rolling hooks' - fishermen's lines with many large hooks attached to them that are strung along the river bed. Others become entangled and drown in some of the many gill nets which line the river's banks. In some areas, the number of dolphins caught in this was has been dramatically reduced, thanks to government intervention. Educational programmes for fishermen and local bans on these bottom longlines have certainly had an impact but fishing gear is still a major hazard.
Many baiji have been found with appalling injuries after collisions with boats and their propellers. The volume of boat traffic on the Yangtze is likely to continue to grow, especially with the recent trend of economic development in China, so the probability of such encounters is bound to increase.
The acoustic disturbance, caused by the heavy river traffic, may also interfere with the dolphin's sensitive sonar, which it relies on the locate food and navigate in the river's turbid waters.
Added to these problems are a suspected reduction in fish resources in the river in the past 40 years, the development of irrigation facilities, proposed new major dam projects and the dumping by innumerable factories of uncontrolled waste into the river, where it is hidden but not lost in the Chang Jiang's natural turbidity.
Lost? Click here for the main index page.