The Yangtze Dolphin otherwise know as Beiji, White Fin, Whiteflag, Pai Chi, or just Chinese River Dolphin is the rarest dolphin on the planet.  They are the only members in their genus.  Their living area stretches over 1700 km from the Three Gorges to the mouth of the Yangtze River.  They can get to 2 to 2.4 meters long and to weights between 70 to 90 kg.  They have a population consisting between the ranges of 60 to 250.  The dolphin has taken a huge dive in population between the years of 1950 and 1984.  In 1950 there were about 6000 Beiji in known record.  By 1984 the population dwindled to a mere 400; their only chance for survival is through captive breeding.  The reason for this devastating drop is because they have constant threats to their survival.  They fight three major threats boat propellers, dams and floodgates blocking fish migration lowering their food supply, and getting hooked by fishermen.  These threats are the cause for them not being able to reproduce.  There is little knowledge about the reproduction of the Beiji.  What is known is that reproduction is at its peak in the two seasons of autumn and spring.  The dolphin feeds on smaller fish either in early morning or during the night.  They feed by using their noses to probe the bottom of the river.  Their eyesight is very poor so they feed near the mouth or banks of the river using echolocation as the majority of their sight.  They are usually seen in groups of 3 or 4 unless there is a good feeding area then they may be seen in groups as large as 7 to 10.  They are seen less and less through time.  Statisticians say they should be completely extinct in within the next few years.  The saddest thing about the Beiji is that they have been in a good portion of Chinese history dating as far back as 2000 years ago on record, and soon they all will be gone and their history will die.