Vol. 57, 2018 (update: 2018.06.27; 07.18) Reproductive Ecology and Biodiversity of Freshwater Eels around Sulawesi Island IndonesiaJun Aoyama1,*, Sam Wouthuyzen2, Michael J. Miller3, Hagi Y. Sugeha2, Mari Kuroki4, Shun Watanabe5, Augy Syahailatua6, Fadly Y. Tantu7, Seishi Hagihara3, Triyanto8, Tsuguo Otake4, and Katsumi Tsukamoto3 doi:10.6620/ZS.2018.57-30
1International
Coastal Research Center, Atmosphere and Ocean Research Institute, The
University of Tokyo, Otsuchi, Iwate 028-1102, Japan (Received 13 December 2017; Accepted 4 May
2018; Communicated by Hin-Kiu Mok) Jun
Aoyama, Sam Wouthuyzen, Michael J. Miller, Hagi Y. Sugeha, Mari Kuroki,
Shun Watanabe, Augy Syahailatua, Fadly Y. Tantu, Seishi Hagihara,
Triyanto Trie, Tsuguo Otake, and Katsumi Tsukamoto (2018) Sulawesi
Island of north-central Indonesia is located in a region where at least
6 species of tropical anguillid eels are present, but the reproductive
ecology and biodiversity of these eels in each area of the Indonesian
archipelago remains poorly understood. Some information about these
species was obtained from collections of their leptocephalus larvae
made during several times of the year and from year-round collections
of their recruitment-stage glass eels at a few locations. A sampling
survey of anguillid leptocephali was conducted in March 2010 in both
the Celebes Sea and Tomini Bay of Sulawesi Island to learn about the
biodiversity and reproductive ecology of the eels in the region.
Twenty-eight anguillid leptocephali were collected at 13 different
stations, with genetic identification indicating that 3 species of eels
had spawned in the two areas. Larvae were more abundant in the Celebes
Sea (N = 21; 16.0-52.1 mm TL) than in Tomini Bay (N = 7; 9.6-54.8 mm).
The abundant 16-21 mm size-class of Anguilla
bornensis in the Celebes Sea indicated that species had recently
spawned there, and spawning had also occurred in Tomini Bay by A. celebesensis (17.4 mm). These
data and previous life history information suggest that A. celebesensis may have two
spawning seasons in the Celebes Sea, but only one main spawning season
in Tomini Bay. Anguilla borneensis
may spawn at several times of the year in the Celebes Sea. Anguilla marmorata and A. biocolor pacifica spawn outside
the Indonesian Seas, with A. marmorata
recruiting in large numbers in the Sulawesi Island region during much
of the year. Other spawning locations of A. celebesensis and A. interioris
likely exist in Indonesian waters. Therefore, further research is
needed to understand the reproductive ecologies and biodiversity of the
tropical anguillid eels in each region of Indonesia in relation to
geographic and climatic factors. Key words: Freshwater eels,
Reproductive ecology, Spawning area, Leptocephali, Sulawesi Island. *Correspondence: E-mail:
jaoyama@aori.u-tokyo.ac.jp |