Rastrelliger Kanagurta Research Articles

Ethanolic duea ching extract in combination with microbial transglutaminase: Strengthening effect on mince gel and cross-linking of myofibrillar proteins from Indian mackerel

Surimi or fish mince gel are popular seafood products worldwide. Lean fish are commonly used as raw material, while dark fleshed fish, especially Indian mackerel, has high fat content and dark color associated with poor gel quality. To improve gel strength, plant extract, particularly from duea ching (Ficus botryocarpa Miq.), rich in polyphenols and calcium could be used as natural protein cross-linker to strengthen gel network. Effect of ethanolic duea ching extract (EDCE) at varying levels in the absence and presence of microbial transglutaminase (MTGase) on gel property of Indian mackerel mince gel prepared from fillets pre-washed for different times (1 and 3 times) was studied. Heat-induced aggregation of myofibrillar protein (MP) from Indian mackerel fillets under different conditions was also investigated. Mince gel prepared from fillets pre-washed for 3 times added with 0.10 % EDCE and 0.5 unit/g of MTGase (3-PWM-MT-0.10) showed the highest breaking force, deformation and textural properties (P < 0.05). Lower autolysis of mince gel was obtained when EDCE, MTGase or in combination were added. However, addition of ECHE decreased whiteness of mince gel, particularly at higher concentrations (P < 0.05). Electrophoretic images revealed the disappearance of myosin heavy chain when MTGase or EDCE in conjunction with MTGase was incorporated. Addition of 0.10 % EDCE, MTGase or both could induce aggregation and enhance setting phenomenon of MP solution as indicated by higher absorbance at 660 nm and storage modulus (G′), respectively. Based on microstructure study, 3-PWM-MT-0.10 had more compact, finer and interconnected structure than other gels. Therefore, the use of EDCE and MTGase at the appropriate levels could be used for improving quality of mince gel from pre-washed Indian mackerel fillets.

ANALYSIS Catch Per Unit Effort (CPUE) AND Maimum Sustainable Yield (MSY) MALE MACKEREL (Rastrelliger kanagurta) FLYING IN THE SAMUDERA FISHING LAND (PPS) KENDARI

The Banda Sea is an Indonesian water body that holds potential for small pelagic fisheries resources. Situated between Sulawesi Island and Maluku, it is part of the Fisheries Management Area Of The Republic Of Indonesia (WPP-NRI 714), Male mackerel (Rastrelliger kanagurta) is one of the fish species with high economic value, greatly favored by the community for consumption. This has led to an increase in its capture rates. Therefore, the research aims to determine the CPUE and MSY of Indian mackerel in the Kendari Ocean Fisheries Port. Data collection was conducted at the Kendari Ocean Fisheries Port from logbooks, and the research lasted from November to December 2023. The results showed that the standard fishing gear used to catch these fish is purse seine. The status of the utilization of the fishery resources is said to be experiencing underfishing. Based on the research results, the maximum sustainable yield (MSY) is 96,386 kg/year, with an optimal fishing effort of 2,300 trips/year (Fox model).

Small in scale big in contribution: evaluating the stock status of indian mackerel (Rastrelliger anagurta) fishery using cmsy and lbb approaches from pakistan, northern arabian sea

Small in scale big in contribution: evaluating the stock status of indian mackerel (Rastrelliger anagurta) fishery using cmsy and lbb approaches from pakistan, northern arabian sea

A multidecadal study of the Malabar upwelling system influencing Indian Mackerel landings along the coasts of Karnataka and Kerala, south-east Arabian Sea

Indian Mackerel (Rastrelliger kanagurta) is an essential small pelagic fishery resource, contributing to nearly 30 % of India's total marine fish landing. However, this species' life cycle and stock status are poorly understood and data deficient. Ocean mesoscale events are also known to influence their landing, besides the environmental factors like- salinity, chlorophyll, and sea surface temperature, affecting these small pelagic fishes' availability, migration, feeding, and reproductive activity. The Malabar upwelling region (southwest coast of India) is a significant upwelling system where upwelling occurs during the monsoon months. The nutrient-rich water increases the productivity of surface water, leading to plankton abundance. This productivity sustains a fishery for several commercially important fishes, mainly small pelagics such as sardines, mackerels, and anchovies, supporting India's most significant coastal pelagic fishery. For understanding the relationship between the target fish and the oceanographic events, in the present study, Pearson's correlation has been estimated between Indian Mackerel landing, rainfall, Sea water temperature at 0, 10, 20, 30, 45, and 50 m depths, mixed layer depth (MLD), their anomalies and occurrences of potential fishing zone (PFZ) lines along the Malabar upwelling region and corresponding coasts of Karnataka and Kerala. Mackerel landing time series showed a significant autocorrelation in four-quarter lag, correlation with rainfall anomaly in one-quarter lag, with PFZ line and MLD in three-quarter lag, and with SWT@50 (Seawater temperature@50 m depth) and SST anomaly in two-quarter lag both in Karnataka and Kerala. Upwelling events, as indicated by the presence of PFZ lines, were found to significantly impact the landings of Indian mackerel along the Karnataka and Kerala coasts. Polynomial equations were used to model the relationship between mackerel landings and these environmental factors, effectively capturing the influence of these parameters on mackerel catch trends.

Deciphering the distribution of Indian mackerel, Rastrelliger kanagurta (Cuvier, 1817) along the Northwest coasts of India

Deciphering the distribution of Indian mackerel, Rastrelliger kanagurta (Cuvier, 1817) along the Northwest coasts of India

Analysis of Morphometric Characteristics of Indian Mackerel (Rastrelliger kanagurta Cuvier, 1816) Landed at the Fish Landing Base Tanjung Luar, East Lombok

Indian mackerel (Rastrelliger kanagurta) is a small pelagic fish species that has economic value to the community. Overfishing without management causes population decline and negative impacts on fish stocks. This study aims to analyze the morphometric characteristics of indian mackerel at Tanjung Luar Fish Landing Base (PPI), East Lombok. Data from 72 fish were collected from January to April 2024 using observation method and quantitative statistical analysis. The results of descriptive analysis showed that indian mackerel landed in Tanjung Luar PPI had average morphometric characteristics such as total length (22.07cm), standard length (18.75cm), fork length (20,35cm), head length (5.23cm), head height (4.47cm), body height (5.7cm), eye diameter (1.32cm), first dorsal fin base length (3.27cm), second dorsal fin base length (2.89cm), pectoral fin base length (2.60cm), ventral fin base length (2.35cm), anal fin base length (2.61cm), tail shaft length (4.14cm), tail shaft height (0.96cm), lower tail fin length (4.28 cm), and upper tail fin length (4.24cm). Fish growth showed an isometric growth pattern, with body parts growing proportionally. The dominant fish sizes caught were in the juvenile category at 18.2-20.6 cm (44%) and adults at 25.7-28.1 cm (28%). However, the large number of juvenile fish caught indicates the potential for overfishing, requiring effective management such as setting minimum size and fishing time to maintain the sustainability of the fish population.

Artificial Neural Networks (ANN) to Model Microplastic Contents in Commercial Fish Species at Jakarta Bay

Jakarta Bay is known as one of the marine ecosystems that have been contaminated by microplastics. Despite massive loads of microplasticcontamination, Jakarta Bay is also habitat to potential commercial fish species, including anchovy Stolephorus commersonnii and mackerel Rastrelliger kanagurta. While information on the microplastic contents and their determining factors is still limited, the goal of this study was touse artificial neural networks (ANN) as a novel and useful tool to model the determinants of microplastic content in fish in Jakarta Bay, using fish weight and length as proxies. Inside the stomachs of S. commersonnii and R. kanagurta, the order of microplastics from the highest to thelowest was fiber &gt; film &gt; fragment &gt; pellet. Based on the RMSE values of 3.199 for S. commersonnii and 2.738 for R. kanagurta, the ANNmodel of fish’s weight + length ~ pellet was found to be the best fitted model to explain the correlation of fish weight and length with microplastic content in the stomach. The results indicate that ANN is suitable for solving large, complex problems in determining and projecting microplastic contents and provides better estimates that can be used to manage R. kanagurta and S. commersonnii along with microplastic contamination threats.

Annual Variation in Proximate Chemical Composition of Fish Sold in Ludhiana Market: Punjab, India

A study was carried out to investigate the nutritional composition of four different fish species (Wallago attu, Labeo rohita, Pangasianodon hypophthalmus, and Rastrelliger kanagurta) sourced from the inland and marine sector comprising both culture and capture fisheries marketed in Ludhiana fish market from September 2021 to August 2022, encompassing four distinct seasons: post-monsoon, winter, pre-monsoon, and monsoon. The proximate parameters including protein, lipid, carbohydrate, ash and moisture content were analysed following the standard methods. The moisture content across the four species ranged from 72.48% to 81.08% in selected fish. Lowest moisture content was recorded during the pre-monsoon season, contrasting with their highest levels during the monsoon season. Protein levels ranged from 9.72% to 18.36% across different seasons. Specifically, P. hypophthalmus displayed the lowest protein content (9.72±0.18%), while R. kanagurta exhibited the highest (18.36±0.18). W. attu, L. rohita, P. hypophthalmus, and R. kanagurta exhibited their lowest lipid content in flesh during the monsoon season, measuring at 0.69%, 1.59%, 9.33%, and 2.47%, respectively, contrasting with their highest levels during the winter season at 1.07%, 2.05%, 11.04%, and 4.05%, respectively. Across different seasons, carbohydrate content varied from 0.23% to 2.04%. R. kanagurta exhibited the lowest carbohydrate values; while L. rohita displayed the highest. Across different species, ash content varied from 1.62% to 4.34%, with the lowest observed in P. hypophthalmus and the highest in W. attu. Overall in fish muscle, water content reached its peak levels while muscle protein content decreased during the monsoon. The decline in protein and the rise in water content of the muscle were attributed to gonadal development and maturation, which depleted muscle protein reserves during the monsoon season. Inverse relationship between moisture and fat content in fish were observed, suggesting that fatty fish typically exhibit relatively lower moisture content. Lower levels of carbohydrate content are found in the total proximate composition of fish muscle, indicating that most of the glycogen in freshwater fish does not significantly contribute to body reserves.

Separation and identification of bacteria producing protease from the intestine of Sillago sihama and Rastrelliger kanagurta

The importance of marine enzymes, especially protease enzymes, made us investigate the presence of these enzymes in the intestines of two fish species of the Persian Gulf (Sillago sihama and Rastrelliger kanagurta). Our investigations showed that initially 29 strains of bacteria were isolated of which 13 colonies had a specific growth in culture medium, and finally only seven strains were capable of producing a strong aura. T1/2 HR08 and S6B1 HR09 are two strains with the largest diameter of the halo around the bacteria, along with 5 other bacterial strains that were selected for more research. The results from the absorption of the supernatant by the spectrophotometer showed that the two strains T1/2 HR08 and S6B1 HR09 had the highest level of enzyme activity and were selected for identification accordingly. Also, the studies conducted with the 16S rRNA gene showed that these bacteria belonged to two genera, Kocuria and Aeromonas, from the Micrococcaceae and Aeromonadaceae families, and the highest similarity of HR08 and HR09 strains, with a similarity of 99% was shown to Kocuria rhizophila strain 8d-S5 (MN062066.1) and Aeromonas salmonicida strain SHY16- (CP038102.1), respectively. Generally, based on the results, these bacterial strains could be a good and ideal source for the production of the protease enzyme, which is used in many different industries.

Relationship length weight and condition factors of mackerel (Rastrelliger kanagurta) landed in Tanjung Tiram Port Batu Bara District North Sumatra Province

This research aims to determine growth patterns and condition factors. Apart from that, it is also to determine the level of gonad maturity and the gonad maturity index. The method used was a quantitative descriptive method by measuring length and weight and then dissection was carried out to observe the level of gonad maturity of male mackerel fish samples landed every week. The number of samples obtained during the August-September 2023 period was 200 individuals. The results of the research show that the equation for the relationship between length and weight is W = 0,00003L²͐⁸⁴⁵⁴⁷, which indicates a negative allometric growth pattern. The highest condition factor was obtained in the 190-191 mm length class with an average of 0,8757 and the lowest in the 185-186 length class with an average of 0,8416. The gonad maturity level of mackerel (Rastrelliger kanagurta) consists of TKG I to TKG IV. The IKG value obtained ranged from 5,616 to 6,375%. The increase in length of male mackerel shows a weak correlation with weight. Meanwhile, the weight of male mackerel had a significant influence on IKG. Keywords: Male mackerel, growth, condition factors, TKG, IKG. Abstrak Penelitian ini bertujuan untuk mengetahui pola pertumbuhan dan faktor kondisi. Selain itu juga untuk mengetahui tingkat kematangan gonad dan indeks kematangan gonad. Metode yang dilakukan adalah metode deskriptif kuantitatif dengan mengukur panjang dan berat kemudian dilakukan pembedahan untuk diamati tingkat kematangan gonad sampel ikan kembung lelaki yang didaratkan setiap minggunya. Adapun jumlah sampel yang diperoleh selama periode agustus-september 2023 adalah sebanyak 200 ekor. Hasil penelitian menunjukkan bahwa persamaan hubungan panjang berat W = 0,00003L²͐⁸⁴⁵⁴⁷ yang menunjukkan pola pertumbuhan allometrik negatif. Faktor kondisi tertinggi diperoleh pada kelas panjang 190-191 mm dengan rata-rata sebesar 0,8757 dan terendah pada kelas panjang 185-186 dengan rata-rata sebesar 0,8416. Tingkat kematangan gonad ikan kembung (Rastrelliger kanagurta) terdiri dari TKG I sampai TKG IV. Nilai IKG yang didapatkan berkisar 5,616-6,375%. Pertambahan ukuran panjang ikan kembung lelaki menunjukkan korelasi yang lemah terhadap berat. Sedangkan berat ikan kembung lelaki memberikan pengaruh yang nyata terhadap IKG. Kata Kunci: Ikan kembung lelaki, pertumbuhan, faktor kondisi, TKG, IKG.

Are Indian mackerel (Rastrelliger kanagurta) populations in the eastern Indian Ocean truly homogeneous? Insights from geometric morphometric analysis

The boundaries of Indian mackerel (Rastrelliger kanagurta) populations/stocks in the three Large Marine Ecosystems (LMEs) in the eastern Indian Ocean (Arabian Sea, Bay of Bengal, and Andaman Sea) are not clearly discriminated or delineated, resulting in conflicting population boundaries. Inherent limitations of the methodologies adopted could be the major reason behind this lack clarity in the population boundaries. Geometric morphometric analysis (GMA) using landmarks has been found to be the most appropriate approach under these conditions. Thus, the present study aims to differentiate between the populations of R. kanagurta in the eastern Indian Ocean (Arabian Sea, Bay of Bengal, and Andaman Sea) by employing GMA of body shape. The results indicate significant differences in body shape between the populations of R. kanagurta inhabiting the eastern Indian Ocean. The variations are primarily observed in the relative sizes of body depth, head, dorsal and anal fins, and the position of eyes, mouth, pectoral, anal, and dorsal fins. The Bay of Bengal populations were mainly characterized with a deeper body, large heads, dorsally oriented eyes, posterior pectoral fins and longer anal and second dorsal fin. Andaman populations were characterized with a more streamlined body, anterior pectoral fins, ventral eyes and shorter anal and second dorsal fins. Arabian Sea population possess an intermediate shape between Bay of Bengal and Andaman populations. These observed variations confirm that R. kanagurta constitutes a discrete population in the eastern Indian Ocean. This study provides valuable information on the population structure of R. kanagurta in the Arabian Sea, Bay of Bengal, and Andaman Sea, which can be useful in fisheries management and conservation efforts.

Trace metals and nutrient analysis of marine fish species from the Gwadar coast

Trace metals are naturally occurring metals found in very small concentrations in the environment. In the context of fish flesh, metals such as copper, calcium, potassium, sodium, zinc, iron, and manganese are absorbed by fish and play vital roles in various physiological functions. However, if these metals exceed the recommended limits set by WHO/FAO, they are termed 'toxic metals' due to their harmful impacts on both the fish and its consumers. Therefore, the present study aims to analyze the levels of protein, lipids, and certain metals—Aluminum (Al), Sodium (Na), Zinc (Zn), Titanium (Ti), Iron (Fe), Copper (Cu), Potassium (K), and Calcium (Ca) in three commercially important marine fishes i.e. Rastrelliger kanagurta, Sardinella abella, and Otolithes ruber. The study also aims to assess their potential impact on human health. The macro-Kjeldhal method and Soxhlet apparatus were used to estimate protein and lipid contents, while atomic absorption spectroscopy (AAS) was used to estimate trace metals found in fishes. The study found that these fish species are valuable sources of protein, lipids, and certain essential minerals. The protein content (CP) in these three species ranged from 63.35 to 86.57%, while lipid content was from 21.05 to 23.86%. The overall results of the trace metal concentrations analyzed in the present study revealed that Aluminum (Al), Sodium (Na), Zinc (Zn), Titanium (Ti), Copper (Cu), Potassium (K), and Calcium (Ca) were found in low concentration or traces and also within suitable ranges as set by WHO/FAO. However, Iron (Fe) was absent in all three species. Moreover, both copper and potassium were found in all three species, while Zinc was present in Rastrelliger kanagurta and Sardinella abella, calcium in Sardinella abella, and sodium in Otolithes ruber only. Titanium was recorded for the first time in S. abella. However, the total health risk assessment associated with these fish food consumption was measured by THQ and TTHQ and found to be less than 1, which shows no potential risk related to trace metals found in these fishes on human health upon their consumption. In conclusion, these commercially important marine fish species were found valuable sources of protein, lipids, and essential trace minerals that are necessary for human health. Thus, the current study provides useful information for the local population to make informed decisions about their daily diets and highlights the importance of sustainable fishing practices to maintain these valuable marine resources by periodical monitoring of their ecosystem.

Transfer Learning Model Application for Rastrelliger brachysoma and R. kanagurta Image Classification Using Smartphone-Captured Images

Prior aquatic animal image classification research focused on distinguishing external features in controlled settings, utilizing either digital cameras or webcams. Identifying visually similar species, like Short mackerel (Rastrelliger brachysoma) and Indian mackerel (Rastrelliger kanagurta), is challenging without specialized knowledge. However, advancements in computer technology have paved the way for leveraging machine learning and deep learning systems to address such challenges. In this study, transfer learning techniques were employed, utilizing established pre-trained models such as ResNet50, Xception, InceptionV3, VGG19, VGG16, and MobileNetV3Small. These models were applied to differentiate between the two species using raw images captured by a smartphone under uncontrolled conditions. The core architecture of the pre-trained models remained unchanged, except for the removal of the final fully connected layer. Instead, a global average pooling layer and two dense layers were appended at the end, comprising 1024 units and by a single unit, respectively. To mitigate overfitting concerns, early stopping was implemented. The results revealed that, among the models assessed, the Xception model exhibited the most promising predictive performance. It achieved the highest average accuracy levels of 0.849 and 0.754 during training and validation, surpassing the other models. Furthermore, fine-tuning the Xception model by extending the number of epochs yielded more impressive outcomes. After 30 epochs of fine-tuning, the Xception model demonstrated optimal performance, reaching an accuracy of 0.843 and displaying a 11.508% improvement in predictions compared to the model without fine-tuning. These findings highlight the efficacy of transfer learning, particularly with the Xception model, in accurately distinguishing visually similar aquatic species using smartphone-captured images, even in uncontrolled conditions.

Microplastics assessment in Arabian Sea fishes: accumulation, characterization, and method development.

Around the globe, plastic has been entering the aquatic system and is ingested by organisms. Identification, optimal digestion method, and characterization of the polymers to trace sources are of growing importance. Hence, the present work investigated microplastics accumulation, digestion protocol efficiency, and characterization of polymers with FTIR analysis in the guts of five fishes (Lethrinus nebulosus, Rastrelliger kanagurta, Acanthopagrus arabicus, Otolithes ruber, and Euryglossa orientalis) from the Karachi coastal area, Arabian Sea. A total of 1154 microplastics (MPs) were ingested by 29 out of 33 fish species (87%). The highest average MP/fish was recorded in Otolithes ruber (54) and the lowest in Rastrelliger kanagurta (19.42). Microfibers were the most abundant shape with the highest numbers (35.52%) as compared to the rest of the MPs identified. Transparent microfibers were recorded as the highest in numbers followed by red, black, blue, and green. In this study, KOH with different concentrations and exposure times along with oxidizing agent hydrogen peroxide was tested (Protocols 3 and 4). Results showed these bases were highly efficient in obtaining optimal digestion of the samples. FTIR analysis confirmed that the majority of the polymers found in the fish guts were polyethylene and polypropylene. This study validated for the first time the presence of these polymers of plastic in marine fish from Pakistan.

Bacterial Pathogens in Processed Frozen Fish Samples from Pune City

Amongst non-vegetarian foods, fish foods include various alive and preserved fishes. The preserved fish and their products include loose and packaged salted, dried and frozen. The frozen fishes and their products are mainly export grade and in very little quantity they are used in local markets. Many times such processed frozen fishes are rejected due to presence of undesirable microorganisms and pathogens. In the present study processed frozen fish samples from local market of Pune city were collected and used for detection and isolation of bacterial pathogens. The fish samples collected were L-Sardine (Sardinella longiceps), Mackerel (Rastrelliger kanagurta), Croaker (Johnius spp.), Ribbon fish (Lepturacanthus savali), Lizard fish (Nodus indicus), Itoyori (Nemipterus peroni) and L-Jacket (Oligoplites saurus). The enrichment and selective media were used to detect and isolate the pathogens in the processed frozen fish samples collected. The bacterial pathogens found in these fish samples were E. coli, Salmonella paratyphi-B, Staphylococcus aureus, Bacillus cereus and Vibrio parahaemolyticus. The attention is needed to control and remove such pathogens from food as it is alarming at safety point of view of consumers.

Reduction in salt fermentation time of Indian mackerel (Rastrelliger kanagurta) using Halobacterium salinarum as a starter culture

Salt fermentation is a preservation technique in which higher salt concentrations areintroduced to inhibit the growth of most spoilage microbes. This process takes severalmonths to attain maturity. The present study was designed to accelerate the fermentationrate and shorten the maturation time employing the haloarchaeal strain Halobacteriumsalinarum (HS1). H. salinarum was inoculated in the salt fermentation medium and thefermentation time and quality were compared to the control salt fermentation withoutinoculation of HS1. The lot inoculated with HS1 matured by the 60th day with higher sensoryscores, whereas the control (C) took 120 days for maturation, indicating that the saltfermentation process can be accelerated using haloarchaea. The final moisture contentat the end of 120 days in the control and HS1 were 56.31 and 56.78% respectively. pHshowed decreasing trend initially and was found to be stable in later phases. Protein contentreduced from 24.29 to 18.95% and 15.03% in control and HS1 respectively. Fat contentfluctuated throughout the fermentation period (6.99 to 8.81%) showing an increasingpattern initially and then a reduction during later stages of fermentation. Trimethylamine(TMA, 3.12 to 14.09 mg%), total volatile base nitrogen (TVBN, 18.23 to 38.35 mg%),alpha-amino nitrogen (AAN, 31.87 to 126.43 mg%) and non-protein nitrogen (NPN,0.18 to 0.83%) contents increased throughout the salt fermentation process but werefound to be within limits suggesting controlled degradation. Present results suggest thatH. salinarum (HS1) as a starter culture can accelerate salt fermentation and maturation canbe attained by 60 days compared to 120 days of maturation time taken by control without HS1. Keywords:Haloarchaea, Halobacterium salinarum, Indian mackerel, Maturation, Salt fermentation

Mackerel Fish (Rastrelliger Kanagurta) Management Strategy at Karangantu Port

The aim of this research is to understand the management strategy for Mackerel Fish (Rastrelliger Kanagurta) at Karangantu Harbor. The research method used by researchers is a quantitative research method. The sample selection in this research used the primary data sampling technique, using a purposive sampling technique. Because the aim of this research was mackerel, sampling was carried out randomly on the fishing fleet that caught mackerel and landed at PPN Karangantu. Meanwhile, the researcher's data analysis used Catch Per Unit Effort (CPUE), Fox Model, Schaefer Model, Walter-Hilborn Model, Clarke Yoshimoto Pooley (CYP) Model, and Schnute Model, as well as analysis of management strategy preparation using qualitative descriptive analysis methods based on MSY values, JTB, and average annual production/catch at Karangantu Harbor. The results of the research show that the correlation coefficient (R2) at 20 days is 0.9537. The r value is close to 1 (one), indicating a close relationship between length growth and fish weight. The condition of the mackerel fishery in the waters of Serang Regency is experiencing a decline. For the management of mackerel, the size of the nets used to catch mackerel should be enlarged so that fewer fish are caught that are smaller than the size at which the gonads first mature.

COMPOSITION OF THE NEW DESIGN OF PAYANG CATCHES IN MAJENE WATERS, MAKASSAR STRAIT

In this study, a new design scottish seine net was used with larger than the general size of the Scottish seine net in the research location. The purpose of this research was to analyze the total catch, species composition and the length of the catch. The study was conducted on one case of a Scottish seine net fishery unit by making a new design of Scottish seine net and then operating it with Scottish seine net fishers in the waters of Majene Makassar Strait. The parameters observed were the fish species caught and the length of each species. From the study results, it was found that the catch of 8 species of fish with total of 15,253 fish in the other bag. The species composition consisted of Shortfin scad (Decapterus macrosoma) 66.48%, Indian mackerel (Rastrelliger kanagurta) 14.42%, Rainbow runner (Elagatis bipinnulata) 7.09%, Mackerel tuna (Euthynnus affinis) 3.83%, Malabar trevally (Carangoides malabaricus) 2.39%, Unicorn leatherjacket (Aluterus monoceros) 2.29%, Skipjack tuna (Katsuwonus pelamis) 2.19% and Goldstripe sardinella (Sardinella gibbosa) 1.31%. The length of the dominant catch Shortfin scad (Decapterus macrosoma) as much as 66.48% ranged from 12.5 - 27 cm with a catchable percentage of 82.53% while Indian mackerel (Rastrelliger kanagurta) as the second highest catch was 14.42% only about 2 ,64% worth catching.

Effect of hot smoking conditions on nutritional quality of Indian Mackerel and Pangasius fish Fillets

Effect of hot smoking conditions on nutritional quality of Indian Mackerel and Pangasius fish Fillets

Some biological aspects of indian mackerel (Rastelliger kanagurta Cuvier, 1817) in Bali Strait waters

Indian mackerel (Rastrelliger kanagurta Cuvier, 1817) is a small pelagic fish species which is the main catch commodity in purse seine and jukung fleets in the Bali Strait waters. Sustainable management is urgently needed for indian mackerel populations in Bali Strait waters to remain sustainable fishery. The availability of basic information such as biological aspects is very important as a fundamental resource in the management of indian mackerel in Bali Strait waters. The aims of this study were to reveal several biological aspects of mackerel such as growth patterns, condition factors, sex ratio, and size at first maturity of indian mackerel in Bali Strait waters. Sampling was carried out in May-September 2018. Samples of fish were taken from purse seine and jukung fleets using trawl nets and gill nets. Fish sample was measured, weighed and dissected to observe the sex and the gonadal maturity stage. The total number of indian mackerel samples was 167 individuals. Mackerel in the Bali Strait waters has a positive allometric growth pattern with fish in good condition. The sex ratio was in an unbalanced condition with the number of male fish being more than the female fish. The size at first maturity was 19.34 cm for male fish and 19.76 cm for female fish.