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Vol. 42 No. 2, 2003
Feeding Habits of the Pantropical Spotted Dolphin, Stenella attenuata, off the Eastern Coast of Taiwan
Ming-Chih Wang1, William A. Walker2, Kwang-Tsao Shao3 and Lien-Siang Chou1,*
1Department of Zoology, National Taiwan University, Taipei, Taiwan 106
2National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, Seattle, WA, USA
3Institute of Zoology, Academia Sinica, Taipei, Taiwan 115
Ming-Chih Wang, William A. Walker, Kwang-Tsao Shao and Lien-Siang Chou (2003) Stomach contents were analyzed from 45 pantropical spotted dolphins, Stenella attenuata,
confiscated by Taiwan police and as by-catches by in fisheries off
eastern Taiwan from February 1994 to November 1995. Mesopelagic prey
species dominated the stomach contents. Sixty-four species of fish made
up 67.5% and 21 species of cephalopods made up 32.5% by number.
Myctophid lanternfishes and enoploteuthid squid accounted for 78.3% of
all prey consumed. The enoploteuthid squid, Enoploteuthis chunii,
was the primary prey and represented 25.8% by number of the total prey,
with an overall occurrence of 66.7%. Results of this study are
generally similar to those at earlier food habits studies conducted on
this species in the eastern tropical Pacific. In both regions, the
ratio of fish and cephalopods consumed and the trophic levels of the
dominant prey were similar. Stenella attenuata
in the eastern tropical Pacific and off the eastern coast of Taiwan are
feeding primarily on myctophid lanternfishes and species of the
cephalopod families Enoploteuthidae and Ommastrephidae. The ANOSIM
analysis demonstrated a significant difference in prey composition by
season. The most numerically abundant prey species, Enoploteuthis chunii,
play an important role in the observed seasonal differences, which
contributed 16.8% to the average dissimilarity between fall-winter and
spring-summer.
Key words: Enoploteuthis chunii, Myctophum asperum, Lanternfish, Otolith, Squid beak.
*Correspondence: Tel: 886-2-23661331. Fax: 886-2-23639902. E-mail: chouls@ccms.ntu.edu.tw
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