At 23:51 on July 5， 2005，inBaiji Aquarium，Institute of hydrobiology， Chinese Academy of Sciences， a Yangtze finless porpoise gave a birth to a male porpoise   successfully。 The Institute of hydrobiology has successfully raised finless porpoises for nine years now。 The young male porpoise is about 70 cm length。

During pregnancy， research staff has been closely monitoring the dynamic mother porpoise， including behavior， appetite， and blood biochemical indicators。 On July 5^th， the staff observed that mother porpoise took less food during the day than normal。 About 21:30， the staff observed that the caudate lobe on the mother was occasionally exposed and the researchers immediately launchplans for a comprehensive observation of the mother dolphin physical state。 At 22:10: Sometimesthe caudate lobe was exposedand sometimes retracted。 22:40， David dolphin caudate lobe exposed in vitro stability， and no longer retracted。 22:45， the caudate lobe is about 10-15 cm。 23:45， David dolphin is delivered about 25-30 cm， at this time， only about one third of the baby porpoise’s body can be shown。 23:51， the mother dolphin suddenly travels to the surface of the water， spraying water， and the small porpoise is finally successfully delivered。 The newborn baby porpoise cannot swim well and still cannot recognize directions。 In order to avoid the baby harming from colliding with the pool wall， scientific research personnel watched it closely and help it。 About one hour after birth， the baby porpoise was more adapted to swimming。 After nearly four hours of birth， the young dolphin swam almost normally， and started to look for its mother。 Both mother and baby can now swim together。 At this point， we can see that the baby dolphin accompanies and travels with his mother， and sometimes keep pace with the mother‘s back。 At 9:00 on July 6， after nine hours of birth， the staff observed the mother breast-feeding her baby。 

This was the first time for this female porpoise as a mother。 So the mother porpoise lacks of first hand experience。 Another female porpoise raised in the Baiji Aquarium have not the experience of pregnancy， so it cannot help the mother 。So they can face server challenges。 However， the mother seemed to know exactly what to do and how to take care of her young after delivering。 

The finless porpoise， commonly known as "Jiang Zhu" is widely distributed in East and South Asia and some marine coastal rivers。 The finless porpoise is divided into three sub-species。 Finless porpoises in the middle and lower reaches of the Yangtze River are commonly known as the Yangtze finless porpoise， which is unique to China， the estimated number in wild is about 1，000。 Yangtze finless porpoise are currently protected in Hubei Tian’ezhou oxbow and in Tongling， Anhui Province in semi-natural environment。 Natural reproduction has been successful in these ex situ conservation sites for several years。 However， It is the first instance that the birth of a finless porpoise in artificial breeding conditions in Baiji Aquarium。