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Vol. 50 No. 6, 2011
Range Patterns of Resident Indo-Pacific Humpback Dolphins (Sousa chinensis, Osbeck 1765) in Xiamen, China: Implications for Conservation and Management
Bing-Yao Chen1, Dong-Mei Zheng2, Jian-Feng Ju1, Xin-Rong Xu1, Kai-Ya Zhou1, and Guang Yang1,*
1Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal Univ., Nanjing 210097, China
2College of Oceanography and Environmental Science, Xiamen Univ., Xiamen 361005, China
Bing-Yao Chen, Dong-Mei Zheng, Jian-Feng Ju, Xin-Rong Xu, Kai-Ya Zhou, and Guang Yang (2011) Because Xiamen, China’s Sousa chinensis
population is under heavy anthropogenic pressure, there is an urgent
need for effective management and protection especially at key sites
which are associated with vessel traffic. In the present paper, the
home range sizes of 21 resident dolphins in Xiamen were estimated, and
interactions of their range sizes with features such as social
clusters, paired or unpaired, coefficients of association (COAs) were
assessed. In addition, various interactions of age class and sex were
also explored. As a result, the mean range sizes based on the minimum
convex polygon (MCP), 95% kernel, and 50% kernel, and the linear
distance were respectively 84.06 km2 , 162.48 km2 , 29.7 km2 ,
and 20.74 km. Individuals’ home ranges were concentrated around the
Jiulong River Estuary and Tongan Bay, corresponding well with 2 social
clusters. Range sizes of the 2 social clusters did not significantly
differ. Paired dolphins (preferred partners) had significantly smaller
ranges than unpaired ones. At the multiple-partner level, dolphins with
more partners had significantly larger ranges than those with fewer
partners. Animals with high COAs had significantly smaller MCP range
sizes and linear distances than those with low COAs. In general, there
were no significant changes of home ranges of individuals in different
age classes of the population. The range sizes of 8 females were
slightly (non-significantly) larger than those of other dolphins of
unknown sex. According to our results, the Jiulong River Estuary and
Tongan Bay are identified as core areas should be given priority
consideration. Further understanding of the overall range pattern of
this population requires cooperation with scientists who work in
neighboring waters of Kinmen I. as well as other nearby populations
along the Chinese coast.
Key words: Association, Kernel, MCP, Range, Resident.
*Correspondence: Tel: 86-025-85891163. Fax: 86-025-85891163. E-mail:gyang@njnu.edu.cn
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