Marine Fisheries : Journal of Marine Fisheries Technology and Management

FRESHWATER STINGRAY FISHERMEN’S INCOME IN MUSI RIVER, PALEMBANG CITY, SOUTH SUMATRA

Nabila Nur Septiani — 2024-11-21

Freshwater stingrays are one of the catches targeted by fishers in the Musi River of Palembang City. However, freshwater stingrays are listed as endangered species by the IUCN, and Indonesian government regulates their preservation. Prohibiting the capture of freshwater stingrays can have significant impact on the livelihoods of fishers around the river. This research was designed to analyze fishers’ income and identify the contribution of freshwater stingray catches toward fishers’ income. According to income analysis, the results show that the average fishers’ income is around IDR 269,542.13 - 655,287.47 per trip per day with an R/C ratio to the total cost is 3.78 in the regular season and 2.14 in the low season. The share of freshwater stingray catches toward the total income ranges from 14.22% to 20.93%.

Keywords: elasmobranch, livelihood, profit sharing, sustainable fisheries

SUITABILITY OF SPATIAL-TEMPORAL HABITAT OF YELLOWFIN TUNA (Thunnus albacares) USING MAXIMUM ENTROPY MODEL IN WEST SUMATRA

Septy Heltria — 2024-11-21

Yellowfin tuna is one of the main catches in West Sumatera waters and has a high economic value. Fishing optimization can be improved through spatial and temporal predictions of fishing areas for effective fisheries management. This research aims to predict fishing areas using an oceanographic data approach through maximum entropy (MaxEnt) modelling. Data collection incorporating sea surface temperature and chlorophyll-a were obtained from the Aqua-Modis satellite in 2022 as well as fishing point data from Ocean Fishing Port (OFP) Bungus. The MaxEnt model shows a good level of accuracy in the West season (AUC 0,860), 1st Transitional season (AUC 0,918), East season (AUC 0,918), and 2nd Transitional season (0,920) The contribution of chlorophyll for one year is more significant, accounted for 75,3%, compared to sea surface temperature, constituted 24,7%. The Sea Surface Temperature (SST) values in West Sumatera waters vary on each season, ranging from 26,4 to 34.5 ℃ and the chlorophyll-a fluctuate between 0,03 and 5,45 mg/m3. The distribution of yellowfin tuna habitat on the map shows that most fishing vessel coordinates are in the Habitat Suitability Index (HSI) HSI value of 0,6 – 0,9. Potential areas for catching yellowfin tuna are around the Mentawai Islands.

Keywords: Chlorophyll-a, HSI, Maximum Entropy Model, Sea Surface Temperature, Yellowfin Tuna

ECONOMIC STUDY OF BLUE SWIMMING CRAB FISHING ACTIVITIES IN JAVA SEA USING ELECTRIC AND SAILING BOAT DESIGN

Nanang Setiyobudi — 2024-11-21

The United Nations has proclaimed the world's commitment to reducing greenhouse gas emissions in the Paris Agreement, and Indonesia has a net zero emissions target by 2060. One of the efforts to support this commitment is by applying environmentally friendly fishing vessel technology using sail and electric propulsion. However, to convince the application, it is necessary to consider several aspects, especially the economic aspect of business investment. This study aims to calculate the estimated cost of boatbuilding and fishing operations for 10 days in the Java Sea using the development of electric sailboat design. The payback period of a feasible investment is then calculated by comparing the revenue from Blue Swimming Crab (BSC) fishing activities. Based on the result, recognizing that with an investment value of nearly 400 thousand USD to purchase the boat, it is reasonable to set a minimum goal of capturing at least 1,2 Ton of crabs per trip, and a minimum of 20 trips annually, thus the payback period takes 10 years.

Keywords: Blue swimming crab, Fishing vessel, Java Sea, Net zero emission, Payback period.

CATCH COMPOSITION AND CATCHABLE SIZE OF LOBSTERS (Panulirus spp) IN LEBAK BANTEN WATERS, INDONESIA

Ndaru Narulita Sani — 2024-11-21

Information on the catch composition and catchable size of lobsters in Lebak waters remains limited, posing challenges for effective fisheries management. This study aims to assess the technical performance of the lobster fishery and analyse catch composition. Data on technical performance were collected through interviews with fishers and lobster collectors using random sampling, while a census approach was applied to measure carapace length and weight for 589 lobsters. A descriptive quantitative analysis was conducted to evaluate the length-weight relationship of lobsters. The findings indicate that fishers predominantly use polyamide monofilament gillnets with a mesh size of 3.5–4.0 inches, operating traditional outrigger boats of 2–3 GT and 7 GT for single-day fishing trips in Lebak waters. Panulirus homarus was the dominant species in the catch. The sex ratio of lobsters was imbalanced, and their growth pattern exhibited negative allometry (b < 3). An assessment of catch sizes against the standards set by PERMEN-KP No. 16/2022 revealed a high proportion of undersized lobsters in the Binuangeun Estuary, including P. penicillatus (78–83%), P. homarus (80–100%), P. ornatus (23%), P. longipes (90–100%), and P. versicolor (65–100%). Similarly, in the Cibareno Estuary, the percentages of undersized lobsters were P. penicillatus (84–100%), P. homarus (98%), P. ornatus (0%), P. longipes (100%), and P. versicolor (92%). These findings highlight the need for stricter management measures to ensure sustainable lobster fisheries in the region.

Keywords: catchable, Lebak Banten waters, length weight, lobster, sex ratio

DESIGN AND DEVELOPMENT OF A DEEP LEARNING-BASED AUTOMATIC FISHERIES LOGBOOK FILLING TOOL

Muhammad Iqbal — 2024-11-21

Filling out a fishery logbook is critical in capturing fisheries to maintain fishery sustainability. However, manual logbook filling often leads to errors in data recording, which can impact the accuracy and quality of fishery data. This study propose the design of an automatic fisheries logbook filling tool based on Deep Learning, called FLOADS (Fisheries Logbook and Detection System). This system consists of instruments placed at the ship's hatch, equipped with a camera capable of detecting fish species, measuring the weight of individual fish passing through, and recording and sending data, along with the ship's position and speed, to a server on land. The development stages of the FLOADS include problem identification, tool design, prototype development, and field testing. The FLOADS prototype consisted of three parts: a fish collection container, a fish sliding area, and an Imaging Box with dimensions of 120 cm × 65 cm × 82 cm. Validation of the YOLOv5 model showed an accuracy rate of 99.07% and an F1-Score of 99.1% for recognizing the Tuna, Cakalang, and Tongkol (TCT) fish species. Field testing was conducted in Palabuhanratu using a 10 GT fishing vessel. The field testing results show that FLOADS performs well on board to detect objects with an accuracy rate of 89.1% and track vessel activities with reasonable accuracy.

Keywords: Deep Learning, DeepSORT, Fisheries Logbook, Measurable Fishing, TCT.

BIOECONOMIC ANALYSIS OF RED SNAPPER (Lutjanus sp.) RESOURCES AT REMBANG REGENCY

Meri Handayani — 2024-11-21

Rembang Regency has quite large fishery potential in 2021, reaching 87,292.9 tonnes in Central Java. One of the catches with high economic value is red snapper (Lutjanus sp.). Red Snapper is a demersal fish obtained from the operation of Danish seine. The purpose of this study was to analyze the condition of red snapper resources in Rembang Regency using the bioeconomic approach of the Gordon-Schaefer model and to analyze the level of utilization and exploitation of red snapper (Lutjanus sp.) in Rembang Regency. The research used a descriptive method with a purposive sampling method to collect a sample of 90 respondents who owned Danish Seine gear at Tasikagung Fishing Port. The results of data processing obtained Maximum Sustainable Yield (MSY) with a C_MSYvalue of 2,002 tons/year, E_MSY of 8,857 trips/year. The Maximum Economic Yield (MEY) calculation obtained a C_MEY value of 1,936 tons/year, E_MEY of 7,241 trips/year, and optimal profit of IDR 74,773,571,716 and the calculation of the Open Access Equilibrium (OAE) where a C_OAE value of 1,194 tonnes/year is obtained, an E_OAE of 14,483 trips/year. The permissible utilization rate of red snapper (Lutjanus sp.) in Rembang Regency is 3,670,532 kg/year. In the last 9 years, an average resource utilization rate of 45% was obtained and an average effort level of 158%. This level of effort has exceeded the fishing limit, so it is necessary to reduce or limit fishing efforts.

Keywords: MSY; MEY; Rembang Regency; Red Snapper; Gordon Schaefer

TUNA FISHERIES IN NORTH SULAWESI: PORTRAIT OF FRESH TUNA DIRECT EXPORT

Ronald S A Posundu — 2024-11-22

The North Sulawesi Regional Government implemented a policy breakthrough to enhance the competitiveness of tuna fisheries by facilitating the direct export of fresh tuna from Manado to Japan. However, export operations have not run optimally, as the cargo quota of 20 tons per trip per week has not been achieved which threatens the continuation of the operation. This study aims to describe the current state of direct export of tuna to Japan and to identify the causes of the failure to meet the cargo quota target for direct export of fresh tuna to Japan. The data used in this study were obtained through in-depth interviews with respondents selected using purposive and accidental sampling, as well as direct observation at the research location. The data were processed qualitatively and quantitatively, and then analyzed descriptively. The results of the study revealed a reduction in the export quota from 20 tons per trip per week to 3 tons per trip per week. In 2023, the export reached the average delivery target was only met in three months: March, April, and December, with 3.35 tons, 3.04 tons, and 7.34 tons, respectively. The cause of the issue is the shortage of high-quality tuna raw materials (grade A), which results from fishermen failing to implement proper fish handling methods during fishing operations. Furthermore, the dependence on tuna supplies from PPS Bitung. The solution is to enhance the ability of fishermen according to good fish-handling standards and to diversify the supply chain of fresh tuna by sourcing from both within and outside the North Sulawesi region.

Keywords: direct export, fresh tuna, North Sulawesi

THE SELECTIVITY OF FISH TRAP ESCAPE GAP SIZE ON BOTANA FISH (Acanthurus reversus)

Agustinus Tupamahu — 2024-11-22

Fish trap is used due to its good prospect, particularly for demersal fish and reef fish in Maluku. A challenge of trap fisheries is the capture of various species of fish, along with a narrow size variation in the captured fish. To reduce the species diversity in the catch and allow the escape of young fish, an escape gap is recommended. This study aims to analyze the effect of different escape gap sizes on the fish that escape and their chances of being caught or escaping relative to the dominant catch. The study was conducted from July to September 2021 in the waters of Eri Village, Nusaniwe District, Ambon City, Indonesia. The experimental fishing method was used in the field. The results indicated that the size of the escape gap had no effect on the number of fish that escaped through each escape gap. The 50% probability of Achanturus reversus escaping from the size 2.0 cm escape gap is in the total length range of 21-22 cm, while from a 3.0 cm escape gap is 24-25 cm.

Keywords: Fish pot, escape gap, selectivity

EFFECTIVENESS OF THE OIL TO GAS FUEL CONVERSION PROGRAM FOR FISHERMEN IN PALEMBANG CITY

Shelia Shelia — 2024-11-22

The Oil to Gas Fuel Conversion Program aims to make it easier for fishermen to obtain fuel at affordable prices, hence they can increase their income. Program implementation is declared effective if it runs smoothly and produces the expected results. This research aims to analyze the effectiveness of the program, analyze the income of program recipients and non-program recipients, and analyze the relationship between program effectiveness and income. Interviews using questionnaires were conducted with research subjects, namely 51 members of the Joint Business Group who received the program and 30 members who did not receive the program. Data in the form of attitudes or opinions of program recipient respondents are analyzed based on the achievement of effectiveness scores, income data from two groups of respondents were analyzed based on the difference between two means tests, and the relationship between effectiveness and income was analyzed based on the Spearman rank correlation test. The research results showed that the program's effectiveness was 94.20% (very high). The t-count value of 4.816 is greater than the t-table of 1.994, indicating that there is a significant difference between the income of program recipients and non-program recipients. The relationship between program effectiveness and income is very weak and not significant, with a coefficient value of 0.032. The effectiveness of the program does not directly affect income, but the existence of the program increases fishing efforts and the income of program recipients.

Keywords: Conversion; effectiveness; fishermen; gas fuel; Spearman Rank Correlation Test

COMPOSITION, LENGTH-WEIGHT RELATIONSHIP, AND FISHING GROUND OF SHARKS LANDED AT PPS CILACAP, CENTRAL JAVA

Yaser Krisnafi — 2024-11-22

This study was conducted to analyze the catches of sharks, such as composition, length-weight relationship, and to determine the distribution of shark fishing areas. Every fishing activity has by-catch issues. Fishers commonly catch sharks as by-catch. These fishing activities will harm the shark ecosystem in the waters. This research was conducted in March – May 2021 at PPS Cilacap. The results of this study showed that A. superciliosus (paitan shark) was a common catches and its total catch was 1,820 kg. The next common catch was Carcharhinus falciformis and the total catch was 723 kg. The lowest catch was the Carcharhinus sorrah shark (sorrah shark) and its total catch was 16 kg. The growth of Carcharhinus falciformis was negative allometric because b-value <3. Meanwhile, the growth of A. superciliosus is positive allometric because b-value was > 3. Length-weight relationship of Carcharhinus falciformis and A. superciliosus was isometric, which means that the growth between length and weight is balanced. Shark fishing areas are located at coordinates 8º - 15º South and 100º - 111º East. The area of shark fishing is at coordinates 8º - 10º South and 108º - 110º East.

Keywords: Composition, Length-Weight Relationship