Understanding the impact of Indian Ocean Dipole (IOD) on fishery around Indonesia is important as the fishery resources are small compared to the demand. In this study, we analyzed the effect of positive and negative phases of IOD on chlorophyll-a concentration and the catch of Sardinella lemuru in the Bali Strait. Data are based on field surveys in the Bali Strait during the positive and negative phase of IOD and Sea Surface Temperature (SST) and Sea Surface Chlorophyll (SSC) obtained from the analysis of satellite images. The results suggest that SSC concentration in the strait significantly correlates with the positive and negative phase of IOD, possibly through a change of upwelling and downwelling there. It is suggested that the change of phytoplankton biomass due to positive IOD would result in an increase of Sardinella lemuru in the Bali Strait. This research has direct implications as important information for the government in planning lemuru fisheries management in the Bali Strait based on oceanographic studies and climate phenomena.

Buku Pengelolaan Sumber Daya Perikanan Laut Berkelanjutan mengulas tentang pemanfaatan perikanan laut bagi generasi sekarang maupun bagi kepentingan generasi masa depan. Dengan kata lain, populasi ikan di laut harus dijaga agar tidak menurun akibat praktik penangkapan ikan yang dilakukan oleh manusia. Perikanan laut Indonesia memiliki potensi yang sangat besar sehingga dapat diandalkan sebagai sumber penting bahan pangan nasional, penghasil devisa negara dari hasil ekspor, penyedia lapangan kerja, serta menjadi sumber pendapatan domestik yang potensial. Jika dikelola dan dimanfaatkan secara optimal, tentu dapat membantu Indonesia dalam mencapai tujuanpembangunan nasional.Pembahasan aspek berkelanjutan menjadi salah satu kekuatan utama yang membuat buku ini bisa menjadi referensi bacaan yang patut diperhatikan oleh pembaca. Selain itu, bahasa yang ringan dan mudah dipahami juga membuat buku ini cocok untuk dibaca oleh berbagai kalangan masyarakat, seperti mahasiswa, akademisi, serta para pegiat lingkungan di komunitas lokalnya masing-masing. Selamat membaca!

Setyohadi D, Rahman MA, Harlyan LI, Rihmi MK. 2024. Species identification and population dynamics of cuttlefish Sepia spp. (Mollusca: Cephalopoda) landed at Brondong Fishing Port, Lamongan, East Java, Indonesia. Biodiversitas 25: 1359-1367. Cuttlefish (Sepia spp.) is one of Indonesia’s fisheries resources with high economic value. It is often caught in the northern Java waters, including Lamongan. As it is high value, cuttlefish resources should be managed to ensure sustainability. However, information on its biology and population dynamics is limited as the basis of fisheries management. This research aimed to identify species of cuttlefish and to estimate its biological aspects and population dynamics. Samples were randomly collected at Brondong Fishing Port from July to September 2022. The result indicated that there were two species of cuttlefish, Sepia aculeata (needle cuttlefish) and Sepia pharaonis (pharaoh cuttlefish), with a proportion of 57.1 and 42.9%, respectively. In addition, S. pharaonis was bigger and heavier than S. aculeata. The mean mantle length = 10.5 cm and weight = 166.6 g for S. aculeata, while S. pharaonis has mean mantle length = 11.4 cm and weight = 208.1 g, and both species have negative allometric growth patterns. Moreover, the asymptotic mantle length (L?) = 24.6 cm and 22.7 cm, growth rate (K) = 0.68 year-1 and 0.78 year-1, total mortality rate (Z) = 1.96 year-1 and 4.61 year-1, natural mortality rate (M) = 0.97 year-1 and 1.64 year-1, fishing mortality (F) = 0.99 year-1 and 2.97 year-1, and exploitation rate (E) = 0.51 year-1 and 0.65 year-1 for S. aculeta and S. pharaonis respectively. This finding might contribute to managing cuttlefish fishery in the north Java waters, especially in East Java.

Cuttlefish (Sepia Spp) Identification and Biological Analysis of A Dominant Cuttlefish Species Landed in Muncar, Banyuwangi Regency, East Java.

Balinese Sardinella (Sardinella lemuru) is the main commodity in Indonesia. Despite, more research show that lemuru got the overfishing condition. In East Java region, likely Bali Strait, Southern-East Java water, and Madura Strait are the region which the most production of lemuru catch. So it needs identification stock of Sardinella lemuru on the third fisheries management east java sub-region, as it to be used as a reference to managing the sustainability of the catch sardinella lemuru for the future. Research carried out in January to May 2016 with the methods is the sample of random sampling on three different locations water representing Madura Strait, Bali Strait, and southern-East Java water. The each sample implemented were in four times during a period of months old different. Every the sample researchers get as 50-200 tail. Sardinella lemuru in accordance with the season fish. The sample which has been obtained taken to the laboratory of Marine Science University of Brawijaya to data take. The analysis used in this research was Truss morphometric and Factor analysis of the condition allometric. Based on the results of the analysis in the Madura Strait, Bali Strait, and Southern-East Java water are having a distinction of morphometric character amount 44 % with the character being very affected is PAL_FL, DFB_HL , PVL_FL, UPCL_FL, OD_HL, and PPL_FL. Around 64 % of the whole morphometric character that is 14 characters. Next, if it is seen from Allometric condition in the third these waters having b value different from each aquatic and after B-test that lemuru in the three the waters might otherwise dissimilar stock so management of Sardinella lemuru in the three waters should have been undertaken in separated.