BIODIVERSITAS ISSN: 1412-033X Volume 23, Number 3, March 2022 E-ISSN: 2085-4722 Pages: 1700-1706 DOI: 10.13057/biodiv/d230362 Short Communication: Genetic variation of oceanic manta ray (Mobula birostris) based on mtDNA data in the Savu Sea, Indonesia MUHAMMAD DANIE AL MALIK 1, , MOCHAMAD IQBAL HERWATA PUTRA 2,3 , EDY TOPAN 2 , NI PUTU DIAN PERTIWI 1,5 , ENEX YUNI ARTININGSIH 1 , SILA KARTIKA SARI 4 , SARAH LEWIS 2,6 , DERTA PRABUNING 2,4 , ANDRIANUS SEMBIRING 1 1 Biodiversitas Indonesia (BIONESIA). Jl. Buluh Indah No. 122, Denpasar 80118, Bali, Indonesia.  email: daniealmalik2@gmail.com 2 Misool Foundation, Savu Sea Program. Jl. Sarotari Timur, Larantuka, Flores Timur 86213, East Nusa Tenggara, Indonesia 3 Elasmobranch and Charismatic Species Program, Yayasan Konservasi Cakrawala Indonesia. Jl. Pejaten Barat Raya No 16A, Ragunan, Jakarta Selatan 12550, Jakarta. Indonesia 4 Yayasan Reef Check Indonesia. Jl. Tukad Balian No. 1A, Denpasar 80226, Bali, Indonesia 5 Biology and Marine Fisheries Department, Faculty of Mathematics and Natural Science, Universitas Pendidikan Ganesha. Jl. Udayana No.11, Buleleng 81116, Bali, Indonesia 6 Manta Trust - Indonesia Manta Project, Indonesia Manuscript received: 7 January 2022. Revision accepted: 26 February 2022. Abstract. Malik MDA, Putra MIH, Topan E, Pertiwi NPD, Artiningsih EY, Sari SK, Lewis S, Prabuning D, Sembiring A. 2022. Short Communication: Genetic variation of oceanic manta ray (Mobula birostris) based on mtDNA data in the Savu Sea, Indonesia. Biodiversitas 23: 1700-1706. The Savu Sea, one of Indonesia's top conservation priorities, is home to various marine charismatic species, including the oceanic manta ray (Mobula birostris), whose conservation status is currently endangered and is protected by the Indonesian government. However, due to domestic and global demand for its fishery products, as well as shortcomings in fisheries management, this species is still poached and bycaught in the Savu Sea. Understanding their population structure is important to achieve effective conservation and fisheries management strategies that will have a positive impact on preserving their population in this area. This study aims to reveal the genetic variation of oceanic manta rays in the Savu Sea. Thirty samples from three locations in the Savu Sea were successfully preserved from East Flores (24), West Manggarai (4), and Rote Ndao (2) and then analyzed using ND5 locus from Mithocondiral DNA (mtDNA). The result indicated a close genetic relationship between three locations (East Flores, West Manggarai, and Rote Ndao) based on the phylogenetic tree and Analysis of Molecular Variance (AMOVA) result with value of 0.05158 (P-value = 0.62268) indicated as a single population. In conclusion, the findings of this study provide some insight into the possibility of manta ray populations in the Savu Sea having strong connectivity between areas, which is critical information for regulators and managers to integrate conservation and management strategies within the Savu Sea. Keywords: Connectivity, fisheries management, genetic INTRODUCTION The Savu Sea is located in the coral triangle area known as mega marine biodiversity (Veron et al. 2009; Foale et al. 2013). This area is an essential habitat for nursery and migratory corridor for marine megafauna (Putra and Mustika 2020; Sahri et al. 2021). The region is known for its complex, high-energy currents, and temperature variation and is an essential habitat for charismatic species such as mobulids rays (Devantier et al. 2008; Lewis et al. 2015). The Savu Sea is also a crucial home for an oceanic manta ray (Mobula birostris) which provides abundant food for this species (Putra et al. 2016; Putra and Mustika, 2020; Putra et al. 2020). In terms of spatial distribution, the Savu Sea with an estimated total area of 23,412 square kilometers is home to the oceanic manta ray (Putra et al. 2020; Figure 1). However, this species has been reported as one of the species targeted by local fisheries, specifically the Lamakeran community (Dewar 2002; Lewis et al. 2015). This community has been fishing for manta rays for generations and has increased their efforts in the last decade as demand for their gill plates grows in Asian markets (Dewar 2002; Lewis et al. 2015). These fishing pressures have had a significant impact on the potential decline in their population in the region, with evidence of a 75 percent reduction in annual landings (Lewis et al. 2015). As a species that has a broad migration pathway (Couturier et al. 2012), efforts to conserve oceanic manta rays focus on international agreements such as the Convention on International Trade in Endangered Species (CITES) and the Convention on Conservation of Migratory Species (CMS) (Stewart et al. 2016). However, the effectiveness of efforts to preserve oceanic manta ray populations in a wide-scale or international approach is still questionable (Stewart et al. 2016). Regional and national strategies such as establishing Marine Protected Areas (MPAs) can effectively manage the oceanic manta ray (Davidson et al. 2015; Graham et al. 2016).