The Importance of Understanding the Current Status of Critically Endangered Species in Shark Fisheries in Muncar, Indonesia

¹ Study Program of Coastal and Marine Resources Management, IPB University (Bogor Agricultural University, Bogor Indonesia
² Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University (Bogor Agricultural University), Bogor, Indonesia
³ The Interdisciplinary Centre for Conservation Science, Department of Zoology, University of Oxford, Oxford, UK
⁴ Department of Resources and Environmental Economics, Faculty of Economics and Management, IPB University (Bogor Agricultural University), Bogor, Indonesia
⁵ Center for Coastal and Marine Resources Studies, IPB University (Bogor Agricultural University), Bogor, Indonesia
⁶ Mobula Project Indonesia, Muncar, Indonesia

^* Corresponding author: osmaleli@apps.ipb.ac.id

Abstract

One-third of all elasmobranch species are classified as globally threatened (i.e., vulnerable, endangered, or critically endangered) according to the IUCN Red List of Threatened Species, The Sphyrnidae family, once among the most abundant shark species complexes, now faces one of highest extinction risks by the IUCN in 2019. This study aimed to analyse the total catch of Sphyrnidae in Muncar, East Java, Indonesia, from 2020 to 2023, and to evaluate the proportion of Sphyrnidae catches relative to other shark during this period. The research utilized both primary and secondary data sources, with daily enumeration conducted, using guidebooks, rulers, hand scales, cameras, code tags, plastic mats, and identification books. The results revealed that most Sphyrnidae catches over the past four years were Sphyrna lewini, with 653 females and 433 males recorded. In contrast, Sphyrna mokarran and Sphyrna zygaena were only landed in minimal numbers over the entire period. Furthermore, S. lewini accounted for less than 15% of the total shark catch, with an average of 58 shark species caught annually. The use of fishing gear by fishers operating vessels under 5 Gross Tonnage (GT) with gillnets in the 10-28 GT range with longlines was identified as significant factor influencing catch composition.”