关键词: 儒艮, 印度洋白海豚, 北部湾

Abstract: Field studies on the dugong ( Dugong dugon) funded by the Ocean Park Conservation Foundation was conducted along the coast of Guangdong , Guangxi and Hainan Provinces from 15 September to 17 November , 2000 to update the information regarding the conservation status of the dugong in the Beibu Gulf . A total of 36 boat surveys were conducted , and 203 questionnaires were collected from people of different occupations. A small group of 5 dugongs was sighted off the coast of Gangmen (19°08′N , 108°39′E) , Dongfang City , Hainan Province on 6 September. According to the questionnaires , at least 2 dugongs were killed accidentally at the end of 1999. The evidence obtained during the surveys indicated that dugongs were greatly reduced in distribution and number compared with those in the 1980s. However , they still existed in some areas in the Beibu Gulf . Based on the results of the surveys , it is suggested that the conservation of dugongs and their habitats along the west coast of Hainan Province should be considered as the highest priority. Groups of 7 and 4 Indian humpbacked dolphins ( Sousa plumbea) were sighted at the mouth of Dafeng River (21°36′N , 108°54′E) , Beihai City , Guangxi Zhuang Autonomous Region on 3 and 4 November , respectively. The small group sighted off the coast of Beihai belonged to the only Sousa plumbea population known to occur in Chinese coastal waters. It is recommended that Sousa plumbea should be included as one of the key protected species in the Guangxi Hepu National Natural Reserve for Dugongs.

Key words: Dugong ( Dugong dugon), Indian humpbacked dolphin ( Sousa plumbea), Beibu Gulf