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The year-class success of small pelagic fish is strongly modulated by the growth and survival of early life stages. Determining how environments control growth is critical to understanding processes influencing annual production. We provide the first measurements of larval growth in Sardinella lemuru, the most abundant and exploited tropical sardine species in the Philippines. Growth rates of larvae were examined across a 2 yr period (2011-2012 and 2012-2013 spawning seasons) using otolith microstructure analysis. Transition to the juvenile stage occurred within 25 to 37 d. Mean growth rate of the 2011 year-class was significantly lower than the 2012 year-class despite significant intra-annual (batch) differences in growth trajectories. In both years, larvae that hatched and developed in the cooler yet prey-rich period in the middle of the spawning season (January) displayed the fastest growth, while those spawned early (September-October 2012) and late (February-March 2012) showed the slowest growth rates. Peak hatch-months (December 2011 and October 2012) were just prior to periods of upwelling, with mean prey concentrations of 0.24 ± 0.13 mg m-3 at 26.35 ± 2.56°C sea surface temperature (SST) and 0.23 ± 0.15 mg m-3 at 26.26 ± 1.79°C, respectively. The SST during upwelling was 0.01 to 1.23°C cooler accompanied by a 0.07 to 0.45 mg m-3 increase in prey concentration. In both years, differences in growth rate were strongly linked to oceanographic conditions. Moderate winds during a ‘neutral’ El Niño-Southern Oscillation year resulted in upwelling conditions favoring faster overall growth in larvae which was associated with stronger recruitment. In contrast, slower growth and weaker recruitment were associated with weak upwelling conditions in the 2011-2012 La Niña year. While temperature may be important, larval growth rates appear to be driven more by prey abundance.

Catch fluctuation of Sardinella lemuru in the Bali Strait in the period 2007 - 2019 shows a significant decrease. The fishermen of this area demanded information on the Potential Fishing Zone (PFZ) specifically targeted for Sardinella lemuru beyond their traditional. PFZ will be very helpful, especially during the famine years. Identification of a Potential Fishing Zone (PFZ) is highly important for increased fishing yields and also reduced fishing time for fishermen. Bali strait is dominated by Sardinella lemuru and contributes 16,2% of the total small pelagic fishery production in Fisheries Management Area (FMA) 573. Bali Strait also supports the fishing industry in Muncar (Banyuwangi-East Java) and Pengambengan (Jembrana-Bali). This study will produce a special PFZ for Sardinella lemuru that is not yet available in Indonesia by using remotely sensed and observer data. Here, we apply the Empirical Cumulative Distribution Function (ECDF) algorithm approach for Sardinella lemuru detection. ECDF was developed using Sea Surface Temperature (SST) and Chlorophyll-a (Chl-a) data from Aqua MODIS and extracted according to observer data during 2011-2014. PFZ for Sardinella lemuru in Bali strait was affected by 72,8 % Chl-a conditions and 27,2% by SST conditions. The maximum suitable preference for Sardinella lemuru in Bali Strait is Chl-a condition at 0,2 mg/m3 and SST condition at 28,38°C in northwest monsoon, while in southeast monsoon are 0,97 mg/m3 for Chl-a and 25,61°C for SST. ECDF model result has 69,33% accuracy, which shows the result of Sardinella lemuru PFZ has good accuracy.

The existence of pelagic fish resources is greatly influenced by the condition of the waters which are described through its relationship with the oceanographic parameters. As a dominant species in Bali Strait, lemuru fish (Sardinella lemuru) have catch dynamics that vary each year. Oceanographic factor influence the number of fish catch in Bali Strait, in which global phenomena such as ENSO and IOD also have a role in influencing the migration of marine resources. This research aims to analysis annual variation of Sea Surface Temperature (SST) and Sea Surface Chlorophyll-a (SSC) in Bali Strait, and its effect on fish catch. The method applied a quantitative descriptive with correlation analysis and spatial analysis using Geographical Information System approach. The analysis described a significant impact of oceanographic parameters on pelagic fish catch. SSC has a significant impact on the number of fish catch which describes a positive correlation, and it illustrated a time interval between the highest concentration of SSC and the period of fishing peak season. It also impacts the fishing trip and the distribution of fishing ground that spread along the area of the Indian Ocean to Bali Strait. SSC has a significant impact on the number of fish catch which describes a positive correlation, and it illustrated a time interval between the highest concentration of SSC and the period of fishing peak season. It also impacts the fishing trip and the distribution of fishing ground that spread along the area of the Indian Ocean to Bali Strait

Lemuru fish (Sardinella lemuru), a small type of pelagic fish, is often found in Indonesia. Lemuru fish oil contains high omega-3 which is benecficial for health. One effort that can be done to optimize the benefits of lemuru fish oil is formulated as an emulsion dosage form. The purpose of this study was to determine the formula and physical stability of the lemuru fish oil emulsion. The method in this study included preparation of emulsions with varian concentration of fish oil (F1: 5%, F2: 10%, and F3: 15%) using natural emulgators (gummi arabicum) and physical stability tests carried out at two temperature variations, 25 o C and 40 o C for 30 days. Physical stability tests included organoleptic, homogeneity, emulsion type, viscosity, pH, and the size of the average globule. The organoleptic test results showed that the three formulas showed phase separation at different time points at both the storage temperatures. The viscosity test results showed that the viscosity of the three formulas has decreased during the storage period. In the emulsion type test it was shown that all three formulas had an oil-in-water (O/W) emulsion type. The pH test results indicated fluctuations during the storage period. The average globul size test results showed that the F3 emulsion formula has a larger average globule size than F1 and F2. In conclusion, the most stable formula was F3 that containing 15% fish oil. F3 was stable for more than 21 days at 25 o C and more than 14 days at 40 o C.

Penelitian ini bertujuan untuk memunculkan bahan baku alternatif lokal untuk mengurangi penggunaan tepung ikan impor dalam formulasi pembuatan pakan untuk budidaya ikan. Uji potensi limbah ikan (kepala dan tulang) tamban atau yang dikenal dengan nama lemuru (Sardinella lemuru) dilakukan melalui uji proksimat kandungan nutrisinya meliputi kadar air, kadar abu, kadar protein, lemak, serat kasar, dan karbohidrat. Analisis proksimat untuk kadar air dengan pemanasan dalam oven bersuhu 105-110 oC, kadar abu dengan pemanasan dalam tanur bersuhu 600 oC, protein dilakukan dengan metode Kjeldahl, lemak dilakukan dengan metode Soxhlet, serat kasar menggunakan metode pelarutan sampel dengan asam dan basa kuat serta pemanasan. Hasil penelitian menunjukkan limbah kepala dan tulang ikan tamban menghasilkan tepung ikan dengan kadar protein 40.68±0.42%.

In lieu of the importance of species authentication of processed fishery products, no reports have been made on sardine products in the Philippines. This is partly because of the challenges in dealing with biological material that has been subjected to extreme conditions during the process. Although molecular tools are now within reach, they are often reliant on proprietary kits which make the process expensive. In this paper, we used hot sodium hydroxide and tris (HotSHOT) DNA extraction protocol and cytochrome oxidase I (COI) minibarcode amplification to genotype and identify selected brands of locally-produced canned and dried sardines. To validate, fresh representatives based on advertised and suspected identities of the processed samples were genotyped as well. Success rate of amplification has gone from 0% to 64% when the minibarcode was amplified, as opposed to using the full-length COI barcoding region. Phylogenetic analysis allowed for the successful identification of processed Sardinella lemuru. Species substitution was detected on samples marketed as dried tawilis; however, the resolving power of minibarcode was not enough to discriminate the samples up to the species level. Regardless, coupling HotSHOT extraction with minibarcode amplification proved to be effective with processed sardines. Using this method to authenticate other processed fishery products that have underwent extreme postharvest processing warrants further exploration.

Tropical sardines (Family Clupeidae) are an important component of many marine fisheries in the Indo-West Pacific region. In Timor-Leste, a small, less-developed country within this region,‘sardiña’are some of the more commonly caught and consumed fish. Yet there is little published information from Timor-Leste about the species composition of these fisheries, nor their biology or ecology. We document the knowledge of Timorese fishers on nine locally distinguished sardine types that contribute to fisheries, and relate these to at least nine species: four species of ‘Flat-bodied Sardinellas’ (Sardinellasubg.Clupeoniaspp.), one species of ‘Round-bodied Sardinella’ (Sardinellasubg.Sardinella lemuru), two species of ‘Tropical Pilchards’ (Amblygasterspp.) and a ‘Tropical Herring’ species (Herklotsichthys quadrimaculatus), all from the Clupeidae family; and oneDussumieriaspecies from the Dussumieriidae family. We record variations in local sardine names across the country and document aspects of fishers’ knowledge relevant to understanding and managing the fisheries, including local sardine species’ seasonality, habitat, movements, interannual variation, as well as post-harvest characteristics in relation to perishability. In general, local names relate more closely with groups of species than individual species, although some names also distinguish fish size within species-groups. The local knowledge identified in this study has immediate application to inform fisheries monitoring and management, and to identify areas for future research. Notably, Timorese fishers recognize and make use of the strong association between some sardine species-groups and seasonally turbid river plumes. While further research is required to understand the underlying mechanisms of this association, this emphasizes the need to consider coastal fisheries and fisher livelihood impacts when assessing any plans or proposals that may alter river flow or water quality. Fishers also recognize migratory behavior of some sardine species, in particular the Flat bodied Sardinellas (S. gibbosaand others) along the north-west coast of Timor-Leste and across the border into Indonesian West Timor. Such insights complicate and need to be accounted for in initiatives for co-management or community-based management of Timor-Leste’s coastal waters and their fisheries.

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.

The purpose of this study was to determine the potential of low commercial value fish species in Lamongan Regency, East Java, Indonesia. The processed data included primary and secondary data. Data were processed using the LQ method and analyzed descriptively by way of compiling data into tables. The survey results showed that there are ten types of low commercial value fish in Lamongan Regency, East Java, Indonesia, namely Sardinella fimbriata (Tembang fish), Leiognathus bindus (Peperek fish), Harpadon nehereus (Puso fish), Sardinella lemuru, (Lemuru fish), Saurida tumbil (Beloso fish), Gerres abbreviatus (Kapasan fish), Anodontostoma chacunda (Juwi fish), and Cynoglossus lingua (Lidah fish). The results of the LQ method showe that there are three types of fish that have the potential to be made of high economic value products, namely L. bindus (11.36), A. chacunda (2.35), and S. fimbriata (2.32). Fish Auction (TPI) that has the potential in terms of fish productivity to be developed is TPI Weru, Lamongan, East Java, Indonesia. The typology of fishermen in TPI Weru has less experience working as a fisherman than other TPI but the level of education is higher and the age of fishermen is younger so that it affects the productivity of fish catches.

Pekalongan fishing port is a fishing base for purse seiners of small pelagic fish in Central Java. Range of fishing fleets Gross Tonnage is 69 to 125 GT. Purse seine was dominant fishing gear with total percentage 84% from the total fishing gear at Pekalongan fishing port in 2014. The main target of purse seine is shoaling pelagic fish. The objectives of this research were to analyze the catch composition and Catch Per Unit Effort (CPUE) of purse seiners at Pekalongan Fishing Port. The method of this research used survey method. Data analysis with quantitative descriptive method. Analysis conducted on the catch composition and Catch Per Unit Effort of purse seiners . Data to analyze the catch composition was secondary data of purse seiners catches volume in 2016 from January until December. And to calculate the CPUE used secondary data of fishing trips and total production of purse seiners from 2008 to 2016. Variations of dominant type of captured i.e. Shortfin scad, Indian scad, Bali Lemuru, and Indian mackerel. Every month there was different of species dominance caught by the gear ranged from 7 to 11 species. The percentage of each species was Shortfin scad ( Decapterus macrosoma ) caught dominantly in January, October, November and December. Indian scad ( Decapterus russelli ) reached the highest percentage in June, July, August and September. Bali Lemuru ( Sardinella lemuru ) mostly caught in February, April and May. While Indian mackerel ( Rastrelliger kanagurta ) caught with highest percentage in March (40%). Location of fishing ground was in Indonesia Fisheries Mangement Area with code 712 and 713. The annual average CPUE of purse seine in Pekalongan Fishing Port was 18,712 kg or 18.7 metric tonnes per trip for each fleet. This result shows that the productivity of purse seiners was quite low compared with the size of fishing fleet Gross Tonnage 69 up to 125 tons.

Sardinella fish ( Sardinella lemuru ) is a species of important pelagic fish from the family of Clupeidae found in Bali Strait. The dynamic condition of Bali Strait makes it fertile which is identical with plankton blooming. The objective of this research was to understand the potential of saxitoxin in sardinella fish because of dinoflagellates consumption in Bali Strait. The research was conducted in Southeast Monsoon (June - August 2015) and Northwest Monsoon (December 2015 – February 2016). The method used was in situ plankton sampling, counting and ELISA test to determine the level of saxitoxin in the fish. Hydro-oceanographic parameters measured were temperatures, salinity, DO (dissolved oxygen), pH level, phosphate level, nitrate level and transparency. They showed average optimum value for phytoplankton growth especially during Southeast Monsoon which its temperature lower and the nutrients (phosphate nitrate) higher than the Northwest Monsoon. This condition caused high richness of phytoplankton in the water and followed with dinoflagellates richness so they accumulated in sardinella fish. It was supported by the analysis of the fish gastric which showed positive correlation between dinoflagellates richness in the water and the fish gastric. ELISA test also showed that saxitoxin level of fish caught in Southeast Monsoon was higher than the one caught in Northwest Monsoon even though the level of saxitoxin was still in the safe range (less than 80 μg STXeq. per 100 g) but the danger of saxitoxin accumulation should be watched out for.

The aim of this research is to know the relationship between lemuru fish catch to Sea Surface Temperature (SST), El-Nino Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) phenomenon in Bali Strait. The results showed, that in the period 2007 – 2016. fluctuations of catches lemuru tends to decline. Sea Surface Temperature (SST) distribution with the lowest temperature 25,28oC at 24,53oC - 27,16oC and the highest temperature is 29,31oC in the range of 28,730C – 30,490C. The lowest temperature occurred in July - September while the highest temperature occurred in January - April. Based on the calculation there is a linkage and relationship between catch and SST as shown on the value of determination and correlation reached 50,0% and 70,73%. Most of the catches occurred in the west season and then the transition II, transition I and East Season. The relationship of ENSO phenomenon to the catch during the El-Nino phase of lemuru catch will increase while in the phase of La-Nina the catch of lemuru will decrease, because time of El-Nino phase of the sea surface temperature (SST) relative low which results in the chlorophyll-a mean case which is a food sources of lemuru fish. Based on Trenberth's theory, (1997), the rise and fall of the ENSO Index of less than six months is not stated in ENSO. From the calculation results during the research of 2007 - 2016 happened three times ENSO phenomenon that is in 2009, 2010 and 2015. At the time of the IOD phenomenon, the IOD (+) phase will result in a decrease in catch while the normal IOD phase and (-) will increase the catch. From the results of this study can also be observed, in the year 2007 - 2011 phenomenon ENSO and IOD have a strong influence on the catch while in the year 2012 - 2016 the influence of the phenomenon of ENSO and IOD has no strong influence caused by the quantity of lemuru fish that have been over exploitation that resulted in the current Bali Strait on Over Fishing status. Keywords : Fish Catch; El-Nino Southern Oscillation (ENSO); Indian Ocean Dipole (IOD)

The objective of this study was to evaluate the effectiveness usage of Indigofera zollingeriana leaf meal (I) and Sardinella lemuru fish oil (L) in diets on the decreasing levels of cholesterol and lipid metabolism of laying duck. One hundred and forty-four Magelang ducks aged 20-32 weeks, laying periode, with an average body weigth of 1,72±0,12 kg were used, which were divided into 6 groups of experimental diets, 3 replications, and of 8 layers each. A completely randomized design, 3x2 factorial design was used in this experiment. The first factor was usage Indigofera zollingeriana leaf meal which replaced protein soybean meal (0%, 5,5%, 11%). The second factor was usage Sardinella lemuru fish oil (0%, 2%). The results showed that the treatment (I5.5L2) was highly significant affected (P

Bali sardinella ( Sardinella lemuru ) is the main fishing catches in Bali Strait . The distribution of S. lemuru and its preferred oceanographic condition were investigated from remotely sensed data. The objectives of this study were to elucidate the distribution of S. lemuru and the preferred oceanographic condition of S. lemuru in Bali Strait using remotely sensed data. Sea surface temperature (SST) and sea surface chlorophyll- a (chl- a ) were downloaded from ocean colour website meanwhile the fishing location generated from daily Visible Infrared Imaging Radiometer Suite (VIIRS) boat detection (VDB), downloaded from NOAA website. The results showed that at the beginning of southeast monsoon (April), most of the fishing location appeared in the north part of Bali Strait, and moved to south part of Bali Strait at the end of the southeast monsoon (September). The results also revealed that most of fishing location of S. lemuru located in SST value of 26 – 30 °C and chl-a value of 0.3 – 0.8 mg/m 3 . Integration VDB data and oceanographic condition generated from remotely sensed data could form the basis for fisheries management and information system, such as S. lemuru in Bali Strait, in the future.

Bali Sardinella ( Sardinella lemuru Bleeker, 1853) was the main catch for fishermen around the Bali Strait waters. The unwell management of the catch effort and the unavailable of allowable catch size were suspected as the factors which made this fish became rare to find in Bali Strait nowadays. In addition, environmental factors were also thought to play a role, for example, the availability of food. This study aimed to reveal the food and feeding habit of Bali Sardinella in Bali Strait waters and their connectivity to the availability of natural food in nature. This study was held for 13 months, from May 2017-May 2018 in three areas of the Bali Strait waters, namely Pengambengan, Pekutatan, and Yeh Leh. Organisms found in the digestive tract of fish were identified until the genera level. The method used for feeding habit was the Important of Relative Index (IRI). Meanwhile, for determining the electivity of the food using the Index of Electivity. Based on the IPR, the food organisms with the highest value were Cyanophyceae ( Trichodesmium ) and Bacillariophyceae ( Nitzshia and Chaetoceros ). The main food varied depending on the season and fish size. Bali Sardinella were planktivorous and chose their food. Plankton which is abundant in the waters was not always found in large quantities in the digestive tract. Abstrak Ikan lemuru ( Sardinella lemuru Bleeker, 1853) adalah salah satu tangkapan utama nelayan di sekitar Selat Bali. Beberapa faktor yang disinyalir menjadi penyebab turunnya produksi ikan ini adalah upaya tangkap yang tidak terkelola baik pada masa lalu dan belum adanya batas ukuran yang boleh ditangkap. Selain faktor penangkapan tersebut, faktor lingkungan juga diduga berperan, misalnya ketersediaan makanannya. Penelitian ini bertujuan untuk mengungkapkan makanan dan kebiasaan makan ikan lemuru di perairan Selat Bali dan keterkaitannya dengan ketersediaan pakan alaminya di alam. Penelitian berlangsung selama 13 bulan, sejak Mei 2017-Mei 2018 di tiga area di perairan selat Bali, yaitu Pengambengan, Pekutatan, dan Yeh Leh. Organisme yang ditemukan di dalam saluran pencernaan ikan diidentifikasi hingga tingkat genera. Untuk kebiasaan makanan ikan, metode yang digunakan adalah Indeks Penting Relatif (IPR). Sementara itu, metode yang digunakan untuk menentukan makanan yang dipilih ikan adalah Indeks Pilihan Jenis Makanan. Berdasarkan nilai IPR, organisme makanan yang nilainya paling tinggi adalah dari kelas Cyanophyceae ( Trichodesmium ) dan Bacillariophyceae ( Nitzshia dan Chaetoceros ). Organisme yang paling banyak dimakan berubah-ubah bergantung kepada musim dan ukuran ikan. Lemuru adalah ikan planktivora dan memilih makanannya. Plankton yang melimpah di perairan belum tentu ditemukan dalam jumlah yang banyak dalam saluran pencernaannya.

The small pelagic fishery in the southern Philippines is one of the largest contributors to fisheries production in the country, and is dominated by the Bali sardine Sardinella lemuru. This species is a year-round spawner that has its peak spawning period during the northeast monsoon (NEM) months of November to February. However, there is still limited information on the conditions that affect this species’ survival during its early life history stages. Here, we attempt to discern the importance of temperature, prey density and advection on sardine larvae. The larvae were represented as passive particles that were released in known spawning grounds to simulate dispersal. The conditions the larvae experienced, namely, temperature and estimated prey density based on satellite chlorophyll-a values were recorded at each time step until the estimated recruitment age of 60 days. The temporal and spatial averaged conditions of recruited sardines showed that sardines spawned during the NEM months experienced higher chlorophyll-a, lower (more optimal) sea surface temperature, albeit higher advective loss, than sardines spawned during other months. Comparisons between years showed that during higher reported catch years, sardine larvae experienced lower temperatures and higher retention nearshore. Our results emphasize that sardine stock management efforts need to recognize the contribution of the temporally variable sardine environment to patterns in sardine recruitment and consequently in catches.

The Bali Strait is one of Indonesia's territorial waters that have high natural resource potential. The area is only about 2,500 km2 but has a high potential fishing ground. The Bali Strait has unique and dynamic waters that can cause fluctuations in fish production amount each year. The largest type of fish caught in the Bali Strait is lemuru (Sardinella lemuru), a fish found only in the Bali Strait. This fish plays a significant role in the economy of fishers in the Bali Strait. Each year the catch of lemuru has fluctuated, making fishing locations challenging to predict. Sea Surface Temperature (SST) and Chlorophyll-a (Chl-a) are oceanographic parameters that can affect the resources of the ocean. Oceanographic phenomena, such as upwelling, can also influence the condition of fish resources. Therefore, understanding the relationships between these factors is essential in practical fisheries management. Observation of oceanographic factors is very hard with the field observation due to time and cost limitations. The remote sensing technique is an efficient method to determine SST distributions and Chl-a concentrations using satellite imagery. This study analyzes SST and Chl-a concentration in the Bali Strait using the Global Change Observation Mission(GCOM-C) satellite and determines the correlation between Chl-a and SST with a total fish catch(lemuru) during 2019. The results showed the maximum average Chl-a concentration observed on August 1.62 mg/m3 and the lowest concentration observed on January 0.45 mg/m3, the maximum SST on March was 28.12° C, and on August (Dry season) with 22.40° C. The SST variable's influence provides a negative correlation (R = -0.209) with changes in lemuru catch, while the Chl-a parameter has a positive correlation (R = 0.375) with changes in the catch. The pattern of relationship between Chl-a with fish catching had a good relationship than the SST in 2019.Keywords: Bali Strait; Sardinella lemuru; SST; Chl-a.

Sardinella lemuru is well known as a dominant fish in Bali Strait. However, since 2010 the stocks have collapsed. Surprisingly, at the end of 2019 it was caught very abundantly in Prigi waters, Trenggalek, reaching 56.42% of the production by volume and 39.44% in value. The reason for this abundance is thought to be the abundant availability of food in nature. This study aimed to analyse the abundance of plankton in relation to the abundance of S. lemuru in Prigi waters at the end of November 2019. A total of 100 S. lemuru samples were caught using a purse seiner, while marine plankton were collected using a 20μm plankton net with a vertical method at 5 sampling sites in S. lemuru fishing grounds in Prigi waters. The morphology, morphometric and meristic characters of the S. lemuru specimens were analysed, as well as the gut contents. Plankton samples collected from the sea and S. lemuru guts were identified and their abundance analysed. The S. lemuru samples had a mean total length (TL) of 16.47 ± 0.19 cm. The plankton from the seawater consists of 52.8% zooplankton and 47.2% phytoplankton, consisting of 21 genera of phytoplankton and 12 genera of zooplankton. Actinocyclus dominated the phytoplankton group with an abundance of 14,098 ind/m3, while the zooplankton group was dominated by Acartia with an abundance of 15,592 ind/m3. Correlation analysis shows the value of the correlation coefficient between phytoplankton in the waters and the S. lemuru was r = 0.920 with a determination coefficient of 84.9%. The abundance of S. S. lemuru in November 2019 was due to the abundant availability of food in the fishing area, when phytoplankton is the main food choice for S. lemuru.

The spatial distribution of lift net (bagan) and the impact on the Sardinella lemuru (lemuru) catches in Senggrong bay - Banyuwangi has been analysed. The data used in this study consists of Pleiades satellite data, aerial photographs of unmanned aerial vehicle (UAV) or drones and in situ measurements in the same period. Fishery data during 2013 to 2017 were analysed to determine the variability of Lemuru catches. The analysis of bagan spatial distribution was performed using visual interpretation technique. Spatial distribution of bagan was analyzed by overlaying data at different period. The results show that the number of bagan in Senggrong bay were 85 unit and spread evenly throughout the bay. In the northwest monsoon, the bagan were spreadedin the northern part of the bay, while in the southeast monsoon, the bagan were shifted to the south due to the high waves and wind speed. Lemuru spawning time was occured in May – July. During spawning time, the amount of Lemuru catches by bagan was relatively low. The peak of lemuru catch was occurred in the period of October to January. The impact of bagan on the decreasing of lemuru abundance is relatively low.

Prigi Waters, East Java, is known as a fishing ground for mackerel tuna and other tunas. However, at the end of 2019, it was found that Bali Sardine (Sardinella lemuru) was a dominant caught that reach more than 56% of the total catch. The reason for the high fish abundance in 2019 is still unknown. Therefore, this study aims to understand the relationship between S. lemuru catch and plankton abundance in Prigi Waters during the high catch event and comparing a similar study in 2017. Plankton abundance was analyzed using the APHA method. Pearson correlation analysis was used to express the relationship between S. lemuru catch and plankton abundance. The result showed that the composition of zooplankton and phytoplankton in waters was 52.8:47.2. Class Bacillariophyceae dominated the phytoplankton group in Prigi waters (47%), where Actinocyclus is the most common genus found (28,762 cell/m3). While in the zooplankton group, the class Maxillopoda dominated (75%), where Nauplius is the most common genus found (34,876 ind./m3). The Pearson correlation analysis showed that S. lemuru catch in November 2019 was greatly influenced by phytoplankton (61.32%) than zooplankton (21.38%) abundances, and the rest was influenced by other factors. High and low plankton abundance in 2019 and 2017 has implications to high and low catch of S.lemuru, respectively. It is suggested that routine and continuous monitoring of plankton may provide good information for fisheries prediction and management in Prigi Waters.

Sardinella lemuru is a small pelagic fish which is mostly caught in Java and Bali waters. It is important because of its high Omega-3 fatty acid. As pelagic fish that are found in relatively shallow waters and near the coast, it could be contaminated from the land. The purpose of this study is to analyse the mercury content of S. lemuru caught in three fishing ground in East Java (Prigi and Muncar) and Bali (Kedonganan). Fish samples were taken by random sampling and collected from November 2019 to March 2020 and analysed for mercury content using the Cold Rapoun Atomic Fluorescence method using the Atomic Absorption Spectroscopy (AAS) Shimadzu AA-6200. Furthermore, the Estimated Daily Intake (EDI) and Maximum Tolerable Intake (MTI) are calculated. The results showed that mercury concentration in S. lemuru were 0.938 ± 0.45 mg/kg and 0.58 ± 0.65 mg/kg for Kedonganan and Prigi, respectively. While, there is undetected mercury for Muncar fish samples. The mercury concentration identified are above the Indonesia standards (SNI and BPOM = 0.5mg/kg). Moreover, the EDI value was higher than Provisional Tolerable Daily Intake -WHO. The mean value of MTI is 0.121 mg/week. If fish contaminated mercury was consumed in one week exceeds the MTI value, the heavy metal could affect the human health.

The frying oil quality decreased during continoiu frying is not only caused by frying condition, but also caused by the food composition of material being fried. The objective of the study was to evaluate the quality changes of frying oil during continous frying of Sardinella lemuru. 12 consecutive batches of frying of lemuru fish were conducted. Frying oil quality changes after 2nd, 4th, 6th, 8th, 10th and 12th batch of frying were evaluated based on determination free fatty acids (FFA), conjugated dienoic acid (CDA), and the smoke point of the oil samples. The results showed that the more repetitions frying the higher levels of FFA and its CDA value while the value of the lower smoke point. Over 12 times in the frying oil quality parameter of FFA still under the limit was broken and starts to break down in the 23rd frying, but the parameters of the CDA value there is no obtained limit demage, while smoke point of the oil begins to break downin 12th frying.

Population genetic structure of Sardinella lemuru in Philippine waters was examined using mitochondrial DNA markers, control region (CR) and cytochrome oxidase I (COI). The sampling effort was focused along the northern coast of Mindanao where the species was previously reported to have regionally structured stocks. Sequences from online databases were included to expand geographic coverage of the analyses. Phylogeographic and population genetic inferences revealed the presence of genetically structured sympatric haplogroups across the archipelago (CR: n = 493, K = 3, between-group genetic distance = 0.038 – 0.054, global Φ ST = 0 . 41 p = 159, K = 2, between-group genetic distance = 0.012, global Φ ST = 0 . 77 , p 0.001). In contrast, little to no genetic differentiation was inferred when samples were assigned based on geographic location (CR global Φ ST = 0 . 01 , p Φ ST = 0 . 001 , p > 0.05). These results suggest that (1) gene flow occurs across space, but is limited among sympatric haplogroups, (2) these sympatric haplogroups do not correspond to cryptic species, and (3) differences in mutation rates between the two markers may have led to a different number of haplogroups being recovered. High haplotype diversity (H CR = 0 . 99 ; H COI = 0 .798), low nucleotide diversity ( π CR = 0 . 041 ; π COI = 0 . 005 ), and significantly negative Fu’s F S values implied demographic expansion for all haplogroups. The mismatch distribution and Bayesian Skyline plot indicated that expansion occurred during the late Pleistocene. Based on our results, we hypothesize that the Philippines is a secondary contact zone for S. lemuru, and testing this requires that samples be obtained from the entire habitat range of the species along the Indo-West Pacific Region.

The complete mitochondrial genome of Sardinella lemuru was sequenced using PCR amplification and primer walking sequence method. The complete mitochondrial genome of S. lemuru was 16,616 bp and contained 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one control region (D-loop). The overall base composition was A 25.04%, C 29.36%, G 20.40%, T 25.20%. In this study, the gene arrangement was consistent with other Sardinella mitochondrial genomes. Additionally, the phylogenetic relationships of 23 Clupeoidei species based on the complete genome was analyzed, and the result showed that S. lemuru firstly clustered with other two Sardinella species, S. albella and S. maderensis. These results would be useful for the investigation of phylogenetic relationship, taxonomic classification and phylogeography of the Clupeoidei.

Studies over the past decade have shown that microplastics are widespread in marine environments, at sea level, on coastlines, and the seabed. Microplastic sources come from small particles used in the cosmetic industry and plastic industry base materials. Other microplastic sources emerge through the degradation of larger pieces of plastic in the environment due to physical and chemical processes, caused by light, heat, oxygen, water, and organisms. Microplastics tend to be digestible by marine organisms and potentially transferred to higher trophic organisms through the food chain, and thus toxic pollutants will potentially harm marine organisms and even humans through bioaccumulation and biomagnification. This research was conducted to determine the characteristics of microplastics that pollute marine fish consumption that is landed in Bali. Samples were gathered from traditional fishermen who landed their catch in Bali. Microplastic is identified in the digestive tract of fish. The samples of fish obtained by Decapterus spp (Selayang), Auxis Rochei (tongkol), Rastrelliger spp (kembung), and Sardinella lemuru (Lemuru). 39 fish out of the total identified 89 fish were found to be contaminated with 69 microplastics (fiber, fragments, film) and 1 mesoplastic (fragment). The size of the plastic found is between 0.32 to 22 mm. The abundance of microplastics in fish caught in Bali's waters is 0.78 (SD 1.15) particles/fish. The finding of microplastics in the digestive tract of fish caught by traditional fishermen in Bali is feared to have the potential to harm marine organisms and even humans through the process of bioaccumulation and biomagnification.

Plastic wastes in marine environment will be degraded for long period of time to become microplastics. The small size of microplastics could be ingested by marine species which has lead to harmful impacts not only to the marine species but also to human. This research aimed to investigate microplastics ingestion in four commercial fishes in the Bali Strait, namely largehead hairtail ( Trichiurus lepturus ), Indian scad ( Decapterus ruselli ), Bali sardinella ( Sardinella lemuru ), and Indian mackerel ( Rastrelliger kanagurta) . Thirty fish samples from each species of fishes were obtained from the fishermen. Microplastics contents were identified visually using microscope from the gastrointestinal tracks of the fish and polymer of microplastics were identified using Fourier Transform Infra-Red (FTIR) test. The results showed that three types of microplastics (fiber, film and fragment) were found in the four species of fishes with different total abundances. The highest abundance was found in Bali sardine (7.03±0.49 particle individual -1 ), followed by Indian mackerel (5.03±0.50 particle individual -1 ), Indian scad (4.23±0.38 particle individual -1 ) and largehead hairtail (3.83±0.50 particle individual -1 ). FTIR test showed that polymer types of microplastic found were polyvinyl chloride (PVC), polyamide (PA), polycarbonate (PC), dan polyethylene (PE).

As a dominant small pelagic fishery in Bali Strait waters, significant decrease of sardine (lemuru) production was bothering fisheries industries, particularly in Muncar and Pengambengan District in East Java and Bali province. Besides of over exploitation, changing environment condition such as temperature, salinity and thermocline depth, indicated the affect on decreasing of sardine production. The interaction among environment variabels, food source availability (Chl-a) and anthropogenic pressure (fishing effort) generate the number of sardine abundance showed by CPUE (Catch per Unit Effort) value that determined sardine production. The current research aims to analyze the simultant impact of changing environment, food availability and antropogenic pressure on sardine CPUE. Field research was conducted in Bali Strait where primary and secondary fisheries data were gathered at Muncar Fishing Port of Banyuwangi District East Java Province and Pengambengan Fishing Port of Jembrana District Bali Province. Oceanography data such as temperature, salinity, and chlorophyll-a profile were collected from INDESO Model. Data analysis was done by time series analysis of each variabels such as CPUE, SST and SSTA, thermocline depth, chl-a and also the number of trip. Partially analysis of those variabels was done by overlayed one another, and principal component analysis determined to analyze the effect of all those varibales simultaneously on sardine CPUE. Results show that there were an influenced of regional climate phenomenon on the dynamic of environment condition of Bali Strait waters, particularly IOD (Indian Ocean Dipole). The CPUE of sardine was determined by the interaction of environment variabels (SST/SSTA, salinity, thermocline depth), food source availabity (Chl-a) and antropogenic pressure (fishing trip) simultaneously, however SSTA gives a significant negative correlation on CPUE. Regional climate phenomenon might cause an extreme condition in Bali strait waters leading to unstable environment for sardine habitat. Drastically changing habitat condition occured under influenced of extreme condition would lead to disruption of sardine CPUE.