Biodiversity of anguilliform leptocephali in the central Indonesian Seas

A sampling survey for leptocephali around Sulawesi Island in the central Indonesian Seas region during May 2001 collected more than 136 species of 11 families of the order Anguilliformes at 25 stations. This high biodiversity of eel species and the wide range of sizes of leptocephali of all families indicated that many species had been spawning during recent months in the region. Leptocephali of the Congridae, Muraenidae, Ophichthidae, Chlopsidae, and Nemichthyidae were the most abundant. All families were widely distributed and there was high species richness and diversity in many areas, suggesting that most taxa of eels were widely distributed throughout the Indonesian Seas. The highest species richness was found in the semi-enclosed Tomini Bay of eastern Sulawesi Island where species diversity was also high at some stations. Anguilla celebesensis Kaup had been spawning in Tomini Bay, but marine eels appeared to have been spawning in most areas. The catch rates of leptocephali varied among areas, with the highest catch rates occurring in Makassar Strait or in Tomini Bay. This first study of the biodiversity of leptocephali in the central Indonesian Seas suggests that many species live in this part of the Indo-Pacific and that eels may be ecologically important components of these high biodiversity ecosystems.