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Contact Name
Maryono
Contact Email
nektonjurnal@gmail.com
Phone
+6282332018483
Journal Mail Official
nektonjurnal@gmail.com
Editorial Address
Jl. Raya Sejangkung Kawasan Pendidikan Tinggi Sambas, Tumuk Manggis, Kec. Sambas, Kabupaten Sambas, Kalimantan Barat 79463
Location
Kab. sambas,
Kalimantan barat
INDONESIA
Nekton
ISSN : 27762742     EISSN : 27762734     DOI : https://doi.org/10.47767/nekton
Penerbitan jurnal NEKTON dua kali setiap tahun, yaitu pada bulan Maret dan Oktober. Ruang lingkup bidang perikanan meliputi agribisnis perikanan, teknologi hasil perairan, budidaya perairan, teknik penangkapan dan pada bidang kelautan terkait ilmu kelautan.
Articles 67 Documents
Seasonal Variability of Wind, Surface Current and Sea Surface Temperature in the Eastern Seram Waters During the 2015 Super El Nino Utama, Cipta; Tubalawony, Simon; Waas, Harold Joppie Davido; Hukubun, Ronald Darlly; Wattimena, Marlin Chrisye
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1062

Abstract

The eastern Seram waters are influenced by both the Seram Sea and the Banda Sea. This study aimed to examine variations in wind, surface currents, and sea surface temperature (SST) during 2015, coinciding with the super El Niño event. Data were obtained from the Group for High Resolution Sea Surface Temperature (GHRSST) and the Copernicus Marine Environment Monitoring Service (CMEMS). The results indicated that the monthly average wind speed in this area ranged from 0.01 to 8.98 m/s, with the lowest speed in November and the highest from January and June to September. Surface currents also exhibited seasonal variability, flowing from the Seram Sea to the Banda Sea during the west season (December–January) and reversing eastward in February. During the east season, Banda Sea water masses were supplied by Seram Sea water. Sea surface temperature decreased notably from June to August, with the lowest temperature recorded in August due to upwelling in the Banda and Arafura Seas. Surface currents formed eddies with warm water centers in the northern part of eastern Seram waters, and cold water centers (25,4 °C) were also observed. The convergence of these two water masses with distinct characteristics generated thermal fronts with temperature differences, resulting in strong temperature gradients from August to October as a consequence of upwelling and cooling induced by the intense El Niño at the end of 2015.
Effectiveness of Soybean Meal as a Feed Supplement on Gonadal Maturation, Gonadosomatic Index (GSI), Hepatosomatic Index (HSI), and Spawning Success of Female Broodstock Catfish Maulidiyah, Vika; Pratiwi, Rizky Kusma; Nurkhasanah, Anissa Aprilia; Masriah, Andi; Mazaya, Amalia Febryane Adhani; Dhia, Maura Yasmin; Firdaus, Fajar Maulana Akmal
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1066

Abstract

The increasing demand for catfish (Clarias sp.) consumption necessitates a sustainable supply of broodstock and seed for aquaculture. One of the main constraints in meeting this demand is the low gonadal maturation rate of catfish outside the natural spawning season. Reproductive hormones play a central role in regulating gonadal maturation through the action of estrogen hormones, particularly 17β-estradiol, which stimulates vitellogenesis or the synthesis of vitellogenin (egg yolk), a major component of oocytes. The increase in vitellogenesis and oocyte size is positively correlated with the level of gonadal maturity. Soybean is a natural source of phytoestrogens that function similarly to estrogen and is rich in linoleic acid, which can stimulate the production of 17β-estradiol. This study aimed to determine the effect of soybean flour supplementation in feed on the Gonadal Maturity Level (GML), spawning success, Gonadosomatic Index (GSI), and Hepatosomatic Index (HSI) of female catfish broodstock. The experimental treatments included a control group (without soybean flour), TK 5% (supplementation of 5% soybean flour per kg of feed), and TK 10% (supplementation of 10% soybean flour per kg of feed). The results showed no significant differences among treatments in terms of GML, spawning success, GSI, or HSI of female broodstock. However, a potential increase in GSI was observed with higher soybean flour supplementation, with the highest GSI value recorded at the 10% dosage level.
Litter Production of Enhalus acoroides and Thalassia hemprichii in the seagrass ecosystem of Tanjung Tiram, Inner Ambon Bay Pasanea, Krisye; Supusepa, Junita; Putri, Amelia
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1074

Abstract

Seagrasses are important primary producers that support marine life. The litter, or fallen leaves, of seagrasses plays a vital role as a source of nutrients in coastal ecosystems. One of the seagrass ecosystems found in Inner Ambon Bay is located in Tanjung Tiram. Studies on litter production have been extensively conducted in mangrove ecosystems; however, in the Maluku region, only one such study has been reported, and no research on seagrass litter production has yet been documented. Litter production serves as an important indicator for assessing coastal ecosystem functioning and blue carbon stocks. Therefore, this study aimed to analyze the litter production of two seagrass species, Enhalus acoroides and Thalassia hemprichii, in the Tanjung Tiram waters of Inner Ambon Bay. The research was conducted from July to August 2025 in the Tanjung Tiram seagrass ecosystem, Ambon City. Litter production was measured using the cage method, constructed from a 3 mm mesh nylon net with dimensions of 0.5 × 0.5 m. Prior to cage installation, the substrate was cleared of existing litter material and benthic organisms, and seagrass density was subsequently estimated. The study period lasted for 3 × 24 hours, with floating and sunken litter collected every 24 hours. The collected litter was oven-dried and weighed to determine dry biomass. Results showed that both E. acoroides and T. hemprichii produced higher amounts of sunken litter (0.0082 g dry weight/shoot/day and 0.0063 g dry weight/shoot/day, respectively) compared to floating litter (0.0062 g dry weight/shoot/day and 0.0028 g dry weight/shoot/day, respectively). The total litter production of E. acoroides (0.0144 g dry weight/shoot/day) was higher than that of T. hemprichii (0.0091 g dry weight/shoot/day).
Length–Weight Relationship of Skipjack Tuna (Katsuwonus pelamis) Landed at Tulehu Village, Maluku Udimera, Rocky; Moniharapon, Domey Lowits; Soukotta, Imanuel V.T.; Rahman, Rahman; Supusepa, Junita
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1081

Abstract

Skipjack tuna (Katsuwonus pelamis) caught in the Banda Sea using purse seines and pole-and-line (huhate) fishing gear has shown a decrease in population size parameters. The parameters observed included size distribution and length–weight relationships, both of which serve as indicators of the size at first capture and first gonadal maturity. This study aimed to analyze the growth pattern of skipjack tuna landed by fishermen at Tulehu fishing port from April to June 2025. The analysis covered fish size distribution and the length–weight relationship. The results showed that the total length distribution of skipjack tuna caught in Tulehu waters reached its highest average in June (24 cm). The highest standard deviation of total length was observed in April (21.7 cm), while the lowest occurred in May (13.4 cm), suggesting that the skipjack population in Tulehu waters represents different recruitment groups. The length–weight relationship obtained was expressed as W = 0.000008 L³·⁰¹⁴⁷, indicating positive allometric growth, meaning that weight increases faster than length. The highest mean weight was recorded in June, with the greatest standard deviation observed in April. Based on these findings, it is recommended that the current size and weight data be used to determine the optimal capture size for skipjack tuna. Furthermore, fish at this stage are in the process of gaining additional body mass, which serves as an energy reserve for spawning activities.
Feasibility Study of a Solar Powered Semi-Submarine (KMP. Mnaibori) as a Model of Sustainable Marine Ecotourism in Raja Ampat Purnawati, Yani Nurita; Pujianto, Andreas; Puspitasari, Asthervina Widyastami; Kurniati, Wenty; Firman, Sri Wahyuni; Sirait, Egbert Josua
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1089

Abstract

This study describes the KMP. Mnaibori, a 14-meter semi-submarine catamaran designed for the waters of Raja Ampat as a model of sustainable marine ecotourism. The objectives are to present the vessel’s design specifications, integrate a hybrid solar–energy system, and assess the financial feasibility and strategic aspects of its development. The methodology includes technical design analysis based on stability, comfort, and underwater observation experience; solar power system performance estimation using the peak sun hours and energy loss factor approach; and financial analysis using Payback Period (PP), Net Present Value (NPV), Profitability Index (PI), Internal Rate of Return (IRR), Break-Even Point (BEP), and Return on Investment (ROI) with a 12% discount rate over a 5-year horizon. The results show that with a solar panel area of 49 m² (38 modules @200 W), the system can generate 21.66 kWh per day. Economically, the project is feasible with a positive NPV of IDR 4.44 billion, a BEP at 12.11 passengers/day (33.6% occupancy), ROI of 49.85% per year, and IRR between 42–45%. SWOT analysis highlights the vessel’s strengths in innovative design and energy efficiency, opportunities in ecotourism growth and green financing support, and challenges related to fuel dependency and weather variability. Development strategies are directed toward service differentiation, solar energy optimization, and enhancing local maintenance capacity.
Closed Transport Engineering of Comet Ornamental Fish (Carassius auratus) using Plant-Based Anesthesia: Effects on Water Quality and Physiological Responses Saputra, Henry Kasmanhadi; Hamka, Muhammad Subhan; Nurussalam, Wildan; Ammar, Muhammad; Supriyono, Eddy; Nirmala, Kukuh
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1093

Abstract

Ornamental comet fish are highly sought after by Indonesians and command high prices. These fish are generally distributed throughout Indonesia in plastic bags using closed transportation. Efforts are made to minimize stress on the fish and reduce the deterioration of water quality during transportation by using the chemical MS 222. However, awareness of the side effects of chemicals has led to the need for organic alternatives. One such solution is the bandotan leaf (Ageratum conyzoides), which contains anesthetic properties. The extraction method for bandotan leaves involves maceration, which is the mixing of bandotan leaves and 96% ethanol in a ratio of 7.5:1. A single factor was used in the experimental design, consisting of 3 treatments and 3 replications, totaling 9 experimental units, with statistical analysis conducted using ANOVA. Metabolic waste plays a role in reducing water quality and physiological responses, which can be suppressed by adding bandotan leaf extract. The treatment with the addition of bandotan leaf extract showed superior results in increasing the Survival Rate (SR). Therefore, bandotan leaf has been proven effective in supporting in good water quality and physiological responses of fish.
Identification and Role of Microalgae Found in Catfish (Clarias gariepinus) Cultivation Pond Inayah, Zakiyyah Nur; Kurniawan, Rahmat Ardi; Aulia, Muhamad Fajar; Pratama, Adif; Islamy, R Adharyan
Nekton Vol 5 No 2 (2025): Nekton
Publisher : Politeknik Negeri Sambas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47767/nekton.v5i2.1096

Abstract

Microalgae play an essential role in aquaculture as primary producers, serving both as natural feed and as bioindicators for assessing pond water quality. The presence of specific microalgal taxa is crucial for evaluating aquatic conditions and identifying potential natural feed sources. This study aimed to identify microalgal species found in African catfish (Clarias gariepinus) culture ponds and to determine their ecological roles. A descriptive survey method was applied. Water samples were collected using a plankton net from three catfish culture ponds during August–September 2025. Identified microalgae were morphologically classified and analyzed for their potential as bioindicators based on literature review using Palmer’s Pollution Index. The results revealed 16 genera belonging to three divisions: Bacillariophyta (diatoms), Chlorophyta (green algae), and Cyanophyta (blue-green algae). Two genera of Bacillariophyta were identified—Aulacoseira and Synedra. Chlorophyta was the most dominant division, comprising 11 genera: Actinastrum, Coelastrum, Dictyosphaerium, Golenkinia, Micractinium, Oocystis, Pandorina, Pediastrum, Scenedesmus, Staurastrum, and Ulothrix. Cyanophyta included three genera—Anabaena, Aphanocapsa, and Spirulina. Among these, Scenedesmus and Pediastrum (Chlorophyta) are commonly used as natural feed, whereas Cyanophyta members are often utilized as water-quality bioindicators. The diversity and abundance of microalgae observed in the catfish ponds indicate organic enrichment, yet they also provide valuable potential as natural feed sources.