Abstract: The authors of the present paper hade made forty-seven sailings in the middle andlower reaches of the Yangtze River for observing the behavior of the Baiji (Lipotes vexillifer), from 1979 to 1990. Based on the records of on the-boat observation, the paper has made a overall description and comprehensive analysis of its behaviors of schooling, mother-calf, feeding courtshipping, playing, resting, escaping, etc., upon its breath on the surface of water.

Key words: Bai ji (Lipotes vexillifer), Behavior, Observation

摘要： 1979--1990年，作者在长江中下游江段，对白暨豚的行为作了47次航行观察。根据观察记录，对白暨豚出水呼吸时所表现的集群、抚幼、觅食、求偶、玩耍、歇息、逃避等行为，作了较全面的描述和分析。

关键词: 白暨豚, 行为, 观察