Some Rare and Endemic Elasmobranchs of Indonesia and Their Conservation Status

Abstract

Indonesia has a very high diversity of sharks and rays that can be found in freshwater and all the way into the deep sea. Some elasmobranchs are considered as endemic species which occur in restricted areas. Comprehensive studies and reviews on the diversity of elasmobranchs in Indonesia have been conducted since 2001 and have resulted in many findings, both of new species and new records. At least 25 species of sharks and rays are known to exist in restricted areas throughout Indonesia. The majority of them are coastal species, the rest are made up of freshwater and deepwater species. Information on the occurrence, distribution and conservation status of some rare and endemic elasmobranchs is provided in this paper. The Bali catshark (Atelomycterus baliensis), spear tooth shark (Glyphis sp.), the giant freshwater ray (Himantura polylepis) and the freshwater ray (Himantura signifer) are just some examples of coastal and freshwater elasmobranchs that are vulnerable to extinction in nature due to anthropogenic and uncontrolled fishing activities. However, there is as yet no management action from the government seeking to protect and conserve these endemic species, mainly due to limited existing data on their biology, ecology and populations.