Growth Characteristic and Conditioning Factors of Mackerel Fish (Scomberomorus commersonii) Landed at PPI Cikidang Pangandaran West Java

Mackerel fish (Scomberomorus commersonii) is one of potential catch in Indonesia. The production of mackerel fish in Indonesia has become the highest in the world exceeding the Philippines, Cingalese, Yemen, and Pakistan. Currently, mackerel fish is used maximumly by considering its sustainability. Present study aimed to understand the growth characteristic and condition factors for mackerel fish which landed at PPI Cikidang, Pangandaran, West Java. The data was collected at PPI Cikidang, Pangandaran, West Java in February 2021. Survey and observation method were used to obtain the growth characteristic of mackerel fish, and it analyzed descriptively. The results of the study revealed that the growth of mackerel fish landed at PPI Cikidang Pangandaran was allometric negative with the b value at 1.71. The growth characteristic based on length-weight relation showed strong relationship with coefficient determination at 93.1%. The condition factor resulted 0.64 with average of relative weight 100.75. The regression relationship between relative weight and condition factors had weak relationship

Factors Affecting the Fitness Rate of Sea Turtle Hatchlings: Systematic Literature Review

The fitness rate is an important indicator for improving survival in the early stages of hatchling's life. This study aimed to determine the fitness rate of sea turtles based on the morphological profile and locomotor performance which includes crawling, self-righting, and swimming performance. The research method used is systematic literature reviews. We found 24 articles published during 2010-2020, which were accessed through Google Scholar, Science Direct, and Springer Link. The results showed that the factors that influence the morphological profile and locomotor performance are sun exposure (12.5%), nest temperature (33.3%); incubation technique (8.3%), sand grain size (8.3%). In addition, the morphological profile and locomotor performance were affected by phenotypic variations of 8.3% and 12.5%; parental origin and nest environment of 8.3% and 4.2%. Factors that only affect locomotor performances are release time and nest digging (4.2%), emergence order, sand temperature, emergence time, nest distance to the sea (4.2%), water temperature (8.3%). Nests that are slightly exposed to sunlight, optimal temperature (30 °C), use coastal hatchery incubation techniques, have a fine sand size (0.5-1 mm), and have phenotypic variations in the form of modal scute patterns produce hatchlings with carapace sizes bigger and greater locomotor performance. Furthermore, higher locomotor performance is obtained if the hatchlings are released immediately after emerge and immediately dug, first emerge hatchlings, have a sand temperature (<36 °C), time to leave the nest before 08.00, nest closer to the sea, warm water temperature (30 °C), and has good environmental conditions

Density and Growth Rate of Nannochloropsis oculata with Different Photoperiods

Nannochloropsis oculata is a type of single-celled or eukaryotic phytoplankton belonging to the class Eustigmatophyceae. This type of microalgae is widely used as natural food for rotifers and fish larvae because it has a high nutritional content. Given this role, many species of Nannochloropsis oculata are cultivated by culture. The success of microalgae culture is influenced by growth factors such as light intensity, CO2, temperature, and nutrition. However, in the process problems often arise regarding the unstable growth of Nannochloropsis oculata. This is usually caused by factors that affect growth, such as light that is not optimal. Based on these problems, it is necessary to conduct research that aims to determine the growth rate of Nannochloropsis oculata with different irradiation treatments. The research method used was an experimental method with 4 treatments i.e., A (24L : 0D), B (12L : 12D), C (18L : 6D), and D (6L : 18D). The results showed that different light exposure period on the density of Nannochloropsis oculata microalgae had no significant effect on their growth rate. Even though the results of statistical tests of photoperiod administration did not affect the production of Nannochloropsis oculata microalgae cell density, the treatment with the dark phase resulted in better growth

Heavy Metal Content of Cadmium (Cd) and Chromium (Cr) in Green Mussels (Perna viridis) and Sediments of Sawojajar Waters, Brebes

Green mussel (Perna viridis) is one of the spesies in Bivalve class which filter the food particles from their surroundings. As filter feeder, it captured anything including plankton, detritus, and even heavy metals. Heavy metals content in green mussels could become dangerous due to the bioaccumulation process. This research aimed to determine the levels of heavy metals Cadmium (Cd) and Chromium (Cr) not only in the tissues of green mussels but also in the sediments of Sawojajar waters, Brebes; current study also determined the feasibility of green mussels for consumption in the perspective of food safety. The method used in this research was a field survey method which conducted in June 2022. The analysis method used AAS refers to the American Public Health Association (APHA) with laboratory tests conducted at the Productivity and Aquatic Environment Laboratory of IPB. The results showed that the content of heavy metal Cd in green mussel samples was at 0.19 mg.kg-1 which was meet the threshold concentration. Whereas, the heavy metal Cr in green mussels’ tissue exceeded the threshold of chromium concentration at 0.21 mg.kg-1. In addition, the heavy metal content of Cd and Cr in sediment were still meet the threshold concentration at 3.2 mg.kg-1 and 0.13 mg.kg-1 respectively. In terms of food safety, the EDI (Estiate Daily Intake) value based on the results of heavy metals Cd and Cr concentrations was 0.11 and 0.13 µg.kg-1.day-1 respectively. The result indicated that these heavy metals concentration had low risk in causing health issue. In the same way, the target hazard value (THQ) of Cd and Cr were not exceeded the RfD (Reference Dose) at 0.109 and  0.036 respectively. These value of THQ for both Cd and Cr indicated low risk in causing cancer and the green mussels are meet the food safety standar

BEBERAPA ASPEK BIOLOGIS IKAN HIBRIDA INVASIF, IKAN LOUHAN DARI WADUK P.B. SUDIRMAN, KABUPATEN BANJARNEGARA, JAWA TENGAH

Ikan louhan atau Flowerhorn Cichlid merupakan spesies ikan hibrida yang dapat ditemukan di hampir semua waduk di Indonesia. Ikan ini dikenal dengan sifatnya yang invasif dan menjadi ancaman bagi ikan asli di berbagai habitat perairan. Akan tetapi, data terkait aspek biologis ikan louhan sangat terbatas. Oleh karena itu, penelitian ini bertujuan untuk menganalisis pertumbuhan dan faktor kondisi ikan louhan sebagai informasi penting dalam pengelolaan populasi ikan invasif ini di Waduk P.B. Soedirman. Sampel ikan dikumpulkan dari pasar ikan tradisional di sekitar waduk pada bulan Juli dan Agustus 2023. Tipe pola pertumbuhan ikan louhan dianalisis menggunakan regresi power. Sebanyak 60 ikan terkumpul terdiri atas 27 ikan jantan dan 33 ikan betina. Panjang total ikan berkisar antara 9.10-19.00 cm. pola pertumbuhan ikan pada bulan Juli adalah isometrik (W=0.0345L2.81). Akan tetapi, pola pertumbuhan pada bulan Agustus menunjukkan pola alometrik negatif (W=0.0666L2.55). Hasil analisis faktor kondisi menunjukkan bahwa ikan berada pada kondisi yang baik pada kedua bulan

Keragaman Morfologi Kerang Hotate (Patinopecten yessoensis) di Teluk Funka Hokkaido Jepang

Hotate scallop are cold water species that can only be cultivated in cold waters. Consumption of Patinopecten yessoensis, Jay 1857 from Japan and other countries shows greater demand, so research related to hotate scallop is important to manage hotate culture and its broodstock to maintain continous supply of this marine product. The purpose of this study is to determine the similarities and dissimilarities morphological characters of hotate scallop in Funka Bay Japan based on landmark characteristics. Data collection technique used was purposive sampling. Morphological measurements was conducted using Image-J software, principle component analysis using PAST software. The results indicate that the level of similarity of hotate scallop in cluster I is 70% and in cluster II is 85%. The principal components of hotate scallop morphometric landmarks is growth line number A20, A21, A22, A23, A25 from total 35 landmarks

Microplastics contamination in commercial fish landed at Lengkong Fish Auction Point, Central Java, Indonesia

Plastic is one of the main pollutant sources that are difficult to decompose and then carried into the ocean and fragmented into smaller parts (microplastics) due to UV radiation and water currents. Their small size means that microplastics are often ingested by aquatic organisms, such as fish. This research aimed to determine the presence, abundance, and types of microplastics in the digestive tract of four dominant fishes landed at Lengkong Fish Auction Point, Cilacap, Central Java, i.e. threadfin (Eleutheronema tetradactylum), mackerel (Rastrelliger sp.), threadfin bream (Nemipterus japonicus), and hairtail (Trichiurus lepturus). We found microplastics in the digestive tract of four selected fishes with a frequency of occurrence of 100%. The concentration of microplastics in fish digestive tracts is relatively high, with a value range of 12 ±2.86 to 28.33 ±8.11 particles∙ind.-1. Microplastics were found in films, fibres, fragments, and granule shape types with various colours: brown, purple, blue, black, green, transparent, and yellow. The polymers found were polystyrene (PS), nylon, acrylonitrile butadiene styrene (ABS), polyurethane (PU), polypropylene (PP), high-density polyethylene (HDPE), and low-density polyethylene (LDPE). The present study provides baseline data for microplastics contamination in commercial fish species landed at Lengkong Fish Auction Point, Cilacap, Central Java, Indonesia. The fact that we discovered PU, the most harmful polymer, piques our attention