Sustainable management of fisheries resources in Java Sea: Utilization status of longtail tuna (Thunnus tonggol) in Indramayu waters West Java case study

Daduk Setyohadi,Djoko Tri L,Affif Rofiiqoh N,Almira Syawli,Muammar Kadhafi,Gatut Bintoro

doi:10.1051/e3sconf/202233904001

Abstract

Longtail tuna (Thunnus tonggol) is a pelagic fish which is generally found in tropical waters. Research on fishery resource sustainability by applying bioeconomic and length weight assessments is necessary to be done in order to determine status of longtail tuna. This research was conducted in south part of Java Sea namely Indramayu waters West Java from January 2020 to April 2020 which aims to estimate utilization status of longtail tuna (T. tonggol) namely exploitation rate, Maximum Sustainable Yield (MSY), Total Allowable Catch (TAC), Maximum Economic Yield (MEY), and Open Access (OA), and to determine length and weight relationship. The research used quantitative descriptive method based on catch and effort data from 2010 to 2019 as well as length weight primary data as much as 987 fish. Result showed that catch and effort at MSY level was 8,453 tons/year and 2,974 trips/year respectively with value of TAC as much as 6,762 ton/year. While the estimated values of catch and effort at MEY level was 8,168 tons/year and 2,427 trips/year with optimum profit as much as 88.98 billion Indonesia dollar rupiah (IDR). Another analysis indicated that OA level was achieved when effort reached at 4,855 trips/year and whilst exploitation rate was 93%. Meanwhile length weight relationship analysis showed that fish had a balance length weight growth which b value = 3.039 with equation W = 0.0147L3.0393. In conclusion, the fish has an isometric length weight relationship and the utilization status of fish is in fully exploited condition hence additional fishing effort must be prohibited in order to maintain stock sustainability.

Highlights

Java Sea, including Indramayu waters, has high potency of marine fisheries resource
Longtail tuna (Thunnus tonggol) is a type of pelagic fish that is oceanodromous and its population is mainly in clear neritic waters. This fish is spread throughout the Indo-West Pacific region from northern Australia, Papua New Guinea and Indonesia, while from the northwest through Malaysia and Thailand, continues to spread to the northeast and south of Japan, northwest of Iran to the Red Sea
The material used in this research is longtail tuna (T. tonggol) caught in Java Sea and landed at the Karangsong Fish Landing Base (FLB), Indramayu, West Java

Summary

Introduction

Java Sea, including Indramayu waters, has high potency of marine fisheries resource. Indramayu Regency has three small islands, namely Biawak Island, Gosong Island and Candikian Island. Longtail tuna (Thunnus tonggol) is a type of pelagic fish that is oceanodromous and its population is mainly in clear neritic waters This fish is spread throughout the Indo-West Pacific region from northern Australia, Papua New Guinea and Indonesia, while from the northwest through Malaysia and Thailand, continues to spread to the northeast and south of Japan, northwest of Iran to the Red Sea. Longtail tuna (T. tonggol) is the second smallest of the eight species Thunnus, growing to a maximum size of 142 cm and a weight of 35.9 kg. Longtail tuna (T. tonggol) is the second smallest of the eight species Thunnus, growing to a maximum size of 142 cm and a weight of 35.9 kg This type of longtail tuna (T. tonggol) is generally the target of fishing in purse seines, gill nets, and line fishing [2]

Methods

Results

Discussion

Conclusion