SPECIES, CONSERVATION STATUS, AND REPRODUCTIVE BIOLOGY OF RAYS (BATOIDEA) CAUGHT BY PURSE SEINE IN BALI STRAIT, INDONESIA

Abstract

This study aimed to analyze the rays (Batoidea) in the Bali Strait, including the caught species, conservation status, and reproductive biology condition. The conservation status is critical to explore as a preventive step from extinction. There is limited data about the conservation status of rays, and it becomes crucial to explore the existence of rays, especially in the Bali Strait. High exploitation without concern on environmental sustainability will cause species to be threatened with extinction due to biological characters in rays, namely low fecundity, long sexual maturity, and slow growth. This research was conducted in December 2019 – March 2020 and found 354 fish. There were 20 species from 15 genera that belong to 7 families. Conservation status is based on the IUCN: three species are CR, three species are EN, eight species are VU, four species are NT, and two species are DD. Meanwhile, six species of rays are included in Appendix II based on the CITES status. There are two species fully protected by the national government. The weight and width relationship of Neotrygon orientalis was negatively allometric, while Taeniura lymma and Mobula thurstoni were positively allometric. The sex ratio of N. orientalis was dominated by male fish, while T. lymma and M. thurstoni were dominant by female fish. Clasper maturity level of N. orientalis, T. lymma, and M. thurstoni was 55%; 56%; 47% and indicated those caught in mature condition. In conclusion, this study has implications on fish management resources to manage the population and conservation status of rays.