Singkarak Lake Research Articles

Strategi Konservasi Daerah Tangkapan Air Danau Singkarak

Land use changes that occur in the upstream areas of the watershed will certainly result in changes in the hydrological characteristics of the watershed. Area expansion in the form of land conversion, whether into residential or agricultural land, in the process often does not pay attention to soil and water conservation principles. Therefore, sustainable water catchment management is needed to reduce increasing land degradation. This research uses the Descriptive Analysis method through the Multidimensional Scaling approach. The sustainability status of the Lake Singkarak catchment area based on the results of the RapDTA analysis is in the moderately sustainable category with an index value of 54.87%. If we look at each dimension that is included in the quite sustainable category, it is the economic dimension with an index value of 55.10% and the social dimension with an index value of 50.37%, while the ecological dimension has an index value of 49.88%.

Aktivitas Promosi Wisata Kuliner Ikan Bilih Sebagai Makanan Khas Danau Singkarak Kabupaten Tanah Datar

The problem studied in this research is culinary tourism promotion activities for bilih fish as a typical food of Lake Singkarak in promoting and marketing bilih fish culinary tourism. Based on these problems, this research aims to describe the marketing promotion activities used by UMKMactors at the Tourism Department in carrying out promotional activities for the Ikan Bilih culinary tourism product. The research approach used is descriptive qualitative. The source of research data is the result of observations of the activities of the Tanah Datar Regency Tourism Office and UMKM actors at Lake Singkarak. Data collection was carried out using observation, interviews and documentation techniques. The theory used is IMC (integrated marketing communications). This theory was put forward to show that the Bilih Fish culinary tourism promotional activities used by Bilih Fish traders in marketing their tourism products are advertising techniques, sales promotions, personal sales "face to face sales", public relations "public relations" Based on the presentation of results based on data and also the results of interviews conducted by researchers, it was concluded that promotional activities for culinary tourism of bilih fish as a typical food of Lake Singkarak, Tanah Datar Regency, it could be concluded that the five promotional communication indicators implemented by UMKM in Lake Singkarak were based on promotion theory. The mix is ​​advertising (public relations), direct marketing (direct marketing), sales (sales promotion), and personal sales (personal sales) fifth in terms of promotions carried out to increase sales of Bilih Fish in Lake Singkarak. Of the fifth indicators, the least dominant among UMKM actors is advertising, in other words there is still a lack of innovation and creativity in promoting it, not all Ikan Bilih MSME actors in Lake Singkarak are able to market Ikan Bilih culinary delights as creatively as possible. The lack of unity between UMKM in terms of pricing also has an impact on sales of Bilih Fish. The role of the Creative Economy Tourism Office is to provide guidance, facilities and financial support to UMKM.

Perahu dan Rumah Gadang

The environment of Lake Singkarak provides natural resources to be utilized by human around it by providing facilities that support their lives. In the water area, of course, boats are needed as a mode of transportation for fishermen. Likewise, markers of settled life in the form of settlements with traditional buildings including ‘Rumah Gadang’. This paper uses qualitative methods with inductive reasoning flows. Data was collected on primary (through observation, observation of object and environment, in-depth interviews) and secondary data. The steps in qualitative research are data collection, analysis, and data synthesis. The purpose of writing is to find out about the sustainability of wood culture on the shores of Lake Singkarak and the local wisdom of the community. The change in manufacture and utilization from dugout canoes to plank boats is an adaptation strategy to the scarcity of sources of Surian wood tree materials. The developed buildings and ornaments also depict the complexion of maritime life (in the lake environment). Nature is a source of inspiration in its motifs and coloring, such as the motif of ‘pucuak rabuang’ (young bamboo), flowers, leaves, fish, and the Dutch royal crown. This is a form of local wisdom of the community in adapting to environmental conditions.

Long-term Change of Water Transparency in Lake Singkarak Observed from Remote Sensing Data

The water quality data for supporting lake management in Indonesia are very limited due to financial constraints. Satellite data has a big potential as a source for providing data to retrieve water quality information. In this study, we used Landsat TM/ETM+ remote sensing data and applied an empirical model for estimating the water transparency (Zsd) to represent water quality in Lake Singkarak. We used 230 scenes of pre-processed Landsat TM/ETM+ images to generate a long-term SD database for Lake Singkarak from 1987 to 2020. The visual and statistical analysis shows the change of Zsd in Lake Singkarak. In the period before 2000, the Zsd were generally lower than 2 meters (m). From 2000 to 2005 the Zsd continuously increased from 1.5m to 4m. Lastly, from 2005 until 2020 Zsd were steady: 2m > Zsd < 4m. The satellite-based Zsd estimations captured the three regimes of water quality in Lake Singkarak. These estimations will thus provide useful data for lake managers and policymakers.

Organochlorine and pyrethroid residue in fish and sediment of Lake Singkarak, a tropical deep lake

Agricultural activities still involve the use of synthetic pesticides to support the increase of their products. On the other hand, the use of synthetic pesticides such as organochlorines and pyrethroids may contribute to the decline of aquatic ecosystem health due to the accumulation of their residues in sediments and organisms. The current study aimed to assess the levels of organochlorine and pyrethroids pesticide residue in endemic fish and sediment from Lake Singkarak. Bilih fish and sediment samples were taken in June 2021 at ten (10) sampling sites in Lake Singkarak. The samples were extracted and analyzed by gas chromatography. Seven organochlorine compounds were measured, including aldrin, endrin, dieldrin, DDT, heptachlor, lindan, and endosulfan. Meanwhile, three compounds chosen from the pyrethroid group, cypermethrin, permethrin, and α-cypermethrin, were also measured. Four organochlorine compounds, aldrin, dieldrin, DDT, and endrin, were detected in bilih fish in three different sites. Dieldrin had the highest concentration at nd-0.007 mg/kg, followed by DDT, endrin, and aldrin. Meanwhile, in the sediments, no organochlorine compounds were detected from all observed sites. Pyrethroid compounds were detected in bilih fish at six sites. The compound with the highest concentration was permethrin (nd-0.02 mg/kg), followed by cypermethrin and α-cypermethrin. The surface sediment from three sites contained two pyrethroid residues, permethrin and α-cypermethrin, at nd-0.002 and nd-0.001 mg/kg, respectively. Our findings show that the residual levels of organochlorine and pyrethroid in bilih fish still meet the standards set by the Codex Alimentarius Commission (CAC). Nevertheless, Bilih fish accumulate more pesticide than surface sediment, so it is essential to be aware of their potential accumulation in the human body as the final consumer. Restriction on synthetic pesticide application is necessary to reduce its residue input into the lake waters for ecological and human health.

Cytotoxic Activities, Determining Toxin, and Molecular Docking of Ovary Pufferfish (Tetraodon leiurus) in Singkarak Lake as Cancer Chemoprevention Candidate

The primary toxin class discovered in freshwater pufferfish is a category of neurotoxins called PSTs (Paralytic shellfish toxins) and pufferfish toxin has been observed to have biological, biochemical, and cytotoxic effects on cancer cell lines. Therefore, it is crucial to determine the cytotoxic activity, toxins present in the ovary of T. leiurus, and interaction between ligand (toxin compound) and receptors test. This study used the MTT method in the T47D cell lines, liquid chromatograph-tandem mass spectrometry (LC-MS/MS), and analysis of the molecular interaction using molecular docking. The ovary of T. leiurus had cytotoxicity on the T47D cell, having an IC50 value of 229.535 μg/ml, and generated a chromatogram with a retention duration of 1.25 min that was similar to the Decarbamoylneosaxitoxin (dcNEO) standard solution. In molecular interactions between the dcNEO ligand to receptors, the lowest ΔG value was -9.29 kcal/mol at the Nav 1.7 receptor, and the lowest KI value was 1.23 µM at the Mcl-1 receptor. These findings indicate that the ovary of T. leiurus is cytotoxic to the T47D cell line and contains dcNEO toxin. It is more stable for the dcNEO ligand to engage with the Nav 1.7 receptor than with other receptors, and it inhibits the Mcl-1 receptor more potently than with other receptors. These findings indicate that the ovary of T. leiurus may be chemotherapy for the prevention of cancer strategy.

Mapping of Chl-a in Indonesia’s Five Priority Lakes uSing Linear Regression (Case Studies: Lake Singkarak, Toba, Maninjau, Matano, and Towuti)

In Indonesia, 15 priority lakes need to be monitored regularly. Model algorithm development is the answer to accelerating lake water quality monitoring through chlorophyll-a concentration monitoring. This research aims to evaluate, develop, and find the most accurate global model algorithm for chlorophyll-a concentration mapping on Lake Singkarak, Toba, Maninjau, Matano, and Towuti. Algorithm development was made based on the existing 22-band ratio algorithm. Leave One Out Cross Validation (LOOCV) was used to evaluate the performance of all tested algorithms through the R2, NMAE, and RMSE accuracy results using 42 in-situ sample points of chlorophyll-a collected on five lakes. Lake Singkarak has an RMSE of 0.1 mg/m3, NMAE of 29.9%, R of 0.7, and R2 of 1.0. Lake Toba in the dry season has RMSE of 0.7 mg/m3, NMAE of 22.5%, R of 0.7 and R2 of 0.3. In the rainy season, Lake Toba has an RMSE of 0.1 mg/m3, NMAE of 7.1%, R of 0.5, and R2 of 0.3. Lake Maninjau has an RMSE of 0.6 mg/m3, NMAE of 32.5%, R of 0.5, and R2 of 0.3. Lake Matano has RMSE of 0.0 mg/m3, NMAE of 4.2%, R of 1.0 and R2 of 1.0. Lake Towuti has an RMSE of 0.0 mg/m3, NMAE of 3.4%, R of 1.0, and R2 of 1.0. The most accurate algorithm for Lake Singkarak, Toba (dry season), Toba (rainy season), Maninjau, Matano, and Towuti are C6, C6, C2, A2, C10, and B3, respectively

Size distribution of bilih (Mystacoleucus padangensis Blkr.) as an endemic fish spatially and temporally using dipp nets in Lake Singkarak, West Sumatra, Indonesia

Lake Singkarak has endemic fish resources of only one species in the world that has economic value, namely Bilih (Mystacoleucus padangensis, Blkr.). The rapid rate of catching using dipp nets fishing gear in this lake is expected to result in a decline in the Bilih population. Dipp nets is a fishing gear that is not environmentally friendly. Bilih fish samples were obtained using dipp nets fishing gear at two locations, namely Intake PLTA (hydropower intake) and Batu Taba for seven (7) months from June to December 2021. The number and size distribution of Bilih were calculated spatially and temporally. The abundance of fish in the Intake PLTA and Batu Taba locations were 472 fish and 716 fish, respectively. As spatially the size range of fish in Intake PLTA is 45-104 mm and in Batu Taba 40-130 mm. The highest fish size is in the 65-72 mm class range, both spatially and temporally (June). Average water quality at Intake PLTA location (temperature 27.87 °C; pH 8.6; DO 4.68 mg/L; Conductivity 0.143 mS/cm; TDS 0.092 mg/L) at a depth of 14.15 m and at Batu Taba location (temperature 28.14 °C, pH 9.24; DO 4.68 mg/L; Conductivity 0.231 mS/cm; TDS 0.092 mg/L) at a depth of 14.15 m.

Linkage analysis of factors influencing the sustainability of Lake Singkarak in West Sumatra Province, Indonesia

Lake Singkarak, located in the West Sumatra Province, resulted from a tectonic process affected by the Great Sumatran Fault. The lake has a total area of 107 km2 and is used for fisheries, tourism, hydroelectric power plant, etc. However, this lake is facing an array of issues and is even considered in a critical condition. Population growth, land use changes, agriculture development, and climate change are suspected to be the causes. It was also aggravated by the COVID-19 pandemic, wherein lake maintenance was neglected. The lake is a system, therefore maintenance of the lake cannot be performed partially and sporadically but must be integrated and comprehensive. This research analyses factors affecting the lake’s sustainability and the linkage between those factors. This research employed a system thinking approach. There are direct and indirect links between social, economic, and environmental factors, as illustrated in a Causal Loop Diagram. This diagram depicts how economic activities are constrained by available potential, which, at certain thresholds, may result in a drop in lake quality if managed in an unsustainable manner. Additionally, lake management appears to be an important factor in overcoming existing issues and establishing a sustainable lake.

Towards sustainable management of Lake Singkarak, Indonesia: System analysis and research priorities

The water use conflicts characterize the inefficiency of the lakes as common pool resources (CPR); therefore, consensus-based collaborative management is one of the best alternative solutions. Tropical lakes supporting multipurpose uses such as clean water sources and fisheries for rural people have diverse and unique characteristics which complicate their management. We engaged the Ecosystem-Based Management-Drivers Pressures States Ecosystem Services Responses (EBM-DPSER) framework to analyze the complex system of Lake Singkarak, Indonesia as a study case. The framework is also used to interlink the system with the Ecosystem Services Framework. This link is crucial to conduct economic valuation of the alternate management responses. We classified several management issues based on the perspectives of local stakeholders and researchers. We highlight our findings, that there are significant discrepancies among the focus and perception of local stakeholders and researchers. The differences result in inefficiency of research fund allocation. Current research activities are focused on biophysical aspects, which have different emphasize with stakeholders’ concerns. Therefore, they do not directly answer decision makers’ questions. The constructed framework aids to align these discrepancies by listing prioritized future research to aid solving the disputes and to promote evidence-based decision making in the lake. We expect that the use of the framework can aid the development of scientific-based consensus management and aid future monitoring and evaluation of various management responses.

Broodstock development, induced spawning and larval rearing of the bilih, Mystacoleucus padangensis (Bleeker, 1852), a vulnerable species, and its potential as a new aquaculture candidate.

Background: Mystacoleucus padangensis living in Lake Singkarak, Indonesia, has high potential market demand but is threatened by overfishing and has not been successfully cultured. This study describes the first broodstock development, induced breeding, and larval rearing of M. padangensis. Methods: A total of 1,000 female and 1,000 male broodfish were collected from the wild and reared in two concrete ponds (128 m 2) at the Centre for Biodiversity Conservation, P.T. Semen Padang, Indonesia. The broodfish were fed commercial feed to satiation at 09:00 and 17:00 h. The females (average weight 7.56 ± 0.85 g) and males (4.86 ± 1.20 g) were selected at a ratio of 1:4 (female:male), and gonad maturation was induced with a single dose of GnRH analogue (Ovaprim) of 0.1 ml/fish. At 16 h after hormone injection, eggs were collected individually into a plastic vessel. Spermatozoa were collected with sterile syringes. Eggs were fertilized using the "dry" method, and 0.5 ml samples (equal to 100 eggs) were taken. The eggs were incubated in a plastic strainer with a water volume of 1.57 litres and placed in a tarpaulin pond with a volume of 150.72 litres. Results: The overall hatching rate was 78.93 ± 4.13%. The newly hatched larvae were 3900.81 µm long, with a yolk sac of 82881.480 µm 2. The mouth opened at 72 days post hatching (DPH) with a gape measuring approximately 61.880 µm. The protocol of larval feeding started with artificial feed, followed by Artemia nauplii up to 30 DPH. Weaning of larvae started at 4 DPH. Larvae started metamorphosis by 15 DPH and ended by 22 DPH when the larvae reached 7430.27 µm. Larval rearing resulted in an average survival rate of 28.4 ± 3.04%. Conclusions: Its successful spawning induction and high larval hatching and survival rates make M. padangensis an excellent aquaculture candidate.

Subsurface Structure of Singkarak Pull Apart Inferred from Magnetic and Gravity Modeling

The existence of active faults along the Sumatran fault has an impact on tectonic activities such as earthquakes and the formation of pull-apart along the Great Sumatran Fault (GSF). The Great Sumatran Fault is segmented into 19 segments. Fourteen segments of which are pull-apart. One of the pull-apart amongofthe GSF is the Singkarak pull-apart which is located on the Sumani segment. Magnetic and gravitational methods are appropriate geophysical methods used to determine rock structures below the earth’s surface. The subsurface structure of the Singkarak pull-apart analysis needed to identify potential future basins. Based on the analysis of the low magnetic anomaly closures on both sides of Lake Singkarak, this study has also succeeded in identifying the presence of a less dense Quaternary Coluvium volcanic deposition outcrop and concluded that the displacement of about 18± 3 km was resulted from a strike-slip process in the past. Furthermore, Lake Singkarak is estimated to have experienced an opening as far as 8 ±1 km which is based on the maximum width of the model profile that passes through the middle of Lake Singkarak.

Organophosphate pesticide residues in surface water and bilih fish (Mystacoleucus padangensis Blkr.) in Lake Singkarak, West Sumatra

Organophosphate pesticide is a pesticide derivate that is used widely by farmers because it has a high killing power against insects and easily disappears from plants. Organophosphate pesticide residues can accumulate in the environment and also cause acute and chronic poisoning in humans. Singkarak Lake in West Sumatra Province is surrounded by many agricultural and farming areas. One of fisheries resources that can be affected by activities at those areas is Bilih fish (Mystacoleucus padangensis). The study aims to determine the levels of organophosphate pesticide residues in Singkarak Lake’s water and Bilih fish. Seven organophosphate pesticide compounds: Diazinon, Fenitrothion, Methidathion, Malathion, Chlorpyrifos, Parathion, and Profenofos were analyzed. In June 2021, surface water and Bilih fish samples were collected from 10 sampling locations in Singkarak Lake. The organophosphate pesticide in the samples was determined using gas chromatography. The results showed that residues were detected in water samples of four locations (Ombilin, Tikalak, Sumani, and Paninggahan), but not in the other six locations (Batu Taba, Sumpur, Guguak Malalo, Saniang Baka, Muaro Pingai, and Tanjung Mutuih) as well as below 1 ppb. Methidathion, Malathion, Chlorpyrifos, and Parathion were detected in lake water at range 2 to 8 ppb. Except for the Bilih fish sample from Ombilin, the majority of the samples contained organophosphate residues. Diazinon, Fenitrothion, Methidathion, Chlorpyrifos, Parathion, and Profenofos were the organophosphate derivate found in the fish samples. Malathion compound was not found. The organophosphate residue concentration in Bilih fish ranged from 2 to 70 ppb.

Lethal toxicity LC50 of permethrin insecticide and its physiological and histopathological effect on common carp and nile tilapia

Permethrin insecticide is commonly used in the worldwide due to the best effectivity in pest control and easier to degrade in the field. However, the implementation in the field of this insecticide is high will cause environmental pollution. It has been reported that aquatic environment at Singkarak lake containing permethrin. The aims of this experiment is to determine of lethal toxicity (LC50) of permethrin insecticide and its physiological effect on common carp and nile tilapia fish. The test fish was common carp and nile tilapia. Insecticide formula with permethrin active agent as a material test was used. Static toxicity method in the laboratorium was performed. Parameters in this experiment observed such as LC50, blood glucose, and histopathological of gill and liver tissues. The result showed that the permethrin insecticide had a high toxic to common carp and nile tilapia with the LC50-96h values were 0.49 dan 0.52 mg/L, respectively. The blood glucose of common carps was ranging from 29.7±0.6–118.3±0.7 mg/DL where the nile tilapia was ranging from 27.7±0.9 – 58.7±1.5 mg/DL. The blood glucose would be increased with increasing the permethrin concentration. The histopathological of gills and liver tissues both of common carp and nile tilapia were hyperplasia and necrosis.

The Development of a Creative Program for Digitizing the Potential of Tourism Villages through Sport Tourism in Singkarak Lake, Solok Regency

Increasing the number of tourist visits to a destination is an indicator of the success of an effective marketing promotion strategy. The selection of an effective marketing promotion strategy that is in accordance with market trends is an absolute must. One of the effective media in the promotion of destination marketing is to use digital marketing media and sport tourism. Lake Singkarak is one of the villages that makes tourism as one of the sectors driving the economy of its people. Lake Singkarak has considerable potential including cultural tourism, nature tourism and educational tourism. Lake Singkarak has a weakness in terms of marketing promotion, so that the increase in the number of visits is not significant.Community service programs are expected to be the solution. Activities carried out are village tourism workshops, and interesting sport tourism to be able to travel on Lake Singkarak.

ESTIMASI POTENSI PRODUKSI IKAN DI DANAU SINGKARAK SUMATERA BARAT BERDASARKAN NILAI KLOROFIL-A DAN KELIMPAHAN FITOPLANKTON

The diversity of fish in marine waters is more than in lakes. However, the lake also has high fishery potential, one of which is Singkarak Lake, Solok Regency. On the island of Sumatra, the first largest lake is Lake Toba, while the second is Lake Singkarak. On the one hand, there are several human activities around the lake that cause a decrease in the production of fish catches, such as fishermen who often catch fish with tools that are not environmentally friendly, are not selective and lead to overfishing. Therefore, the purpose of this research is to examine the potential for fish production in Lake Singkarak based on the value of chlorophyll-a and abundance of phytoplankton. The method used is a survey method. The data analysis process includes analysis of fish production potential on the value of chlorophyll-a and analysis of fish production potential on phytoplankton abundance. Based on the chlorophyll-a value, the estimated fish production potential in Singkarak Lake is 4,663 tons/year and based on the abundance of phytoplankton, the fish production potential is 21,852 tons/year.

A 48-MW floating photovoltaic design and integration to a grid

Photovoltaic is one of the renewable power sources with the highest growth in recent decades. However, large photovoltaic capacities require enormous areas for installing the modules, which is frequently troublesome. This issue could be addressed by a floating photovoltaic system since it can be installed on the surface of unutilised lakes, and dams. This study aims to design a 48-MW floating photovoltaic at Lake Singkarak and determine a connected substation to the West Sumatra Grid. PVsystem and digsilent powerfactory were used in this study as the calculation and simulation tools. The study’s results discover that the 48-MW floating photovoltaic design consists of 96,000 photovoltaic modules of 500 Wp and 16 inverters of 3,000 kVA. Simulation results showed that Solok substation is the most optimum choice to connect the floating PV, as it provides better voltage profiles, fewer power losses and a shorter distance. The harmonic simulation also showed the THDv of 2.14% at 150 kV of Solok substation, which is still within acceptable limits.

Environmental Study for the Conservation of the Simawang Megalitic Site, Lake Singkarak, West Sumatera

The Menhir Simawang site is located in the northeastern part of Lake Singkarak on a hillside with residential areas in the valley. The uniqueness of the Menhir Simawang site is located on a hill facing northeast, where Mount Sago is located. This mountain is one of the mountains that was considered sacred in the minds of the Minang people in the past. The aim is to find out in advance the local wisdom of the Simawang people in the past in adapting to their environment. The second utilizes environmental studies for site conservation. This study uses qualitative methods, using inductive reasoning. To sharpen environmental analysis in conservation, primary data (field) and secondary data analysis is carried out through maps. The excavation results show that the menhirs are related to the burial pits which are oriented northeast-southwest. The selection of a burial site on the top of a hill and the division of its terraced space is one of the implementations of the concept and social structure, as well as the beliefs of the Simawang people. The belief that when someone dies, the spirit will return to the top, so to bring it closer to the upper world, it must be placed in a higher place than their settlement. Local wisdom in choosing land as a grave or settlement is a form of human adaptation to the environment. This local wisdom can be a lesson for us today.

The importance of DNA barcode reference libraries and selection primer pair in monitoring fish diversity using environmental DNA metabarcoding

Abstract. Roesma DI, Tjong DH, Syaifullah, Nofrita, Janra MN, Prawira FDL,Salis VM, Aidil DR. 2023.The importance of DNA barcode reference libraries and selection primer pair in monitoring fish diversity using environmental DNA metabarcoding. Biodiversitas 24: 2251-2260. Environmental DNA (eDNA) metabarcoding has become an alternative method used for biodiversity monitoring of an ecosystem. The eDNA metabarcoding has advantages compared to the conventional method because it is non-invasive, quick, and requires less cost. However, the effectiveness of the eDNA method is highly dependent on the coverage of the DNA barcode reference and primerpair. A study using the eDNA method was conducted for fish biodiversity monitoring in Singkarak Lake. Two-liter water samples were collected using sterile bottle samples at each sampling site (five sites). The universal primers (Fish FI and Fish R1) used for Next-generation sequencing (GRIDION, Nanopore, Oxford Technologies). The study detected 152 fish species using eDNA metabarcoding. Ten species out of the 30 originally reported in Singkarak Lake were detected using eDNA metabarcoding. The low percentage of fish detected is thought to be due to several factors; incomplete/unavailability of freshwater fish DNA barcodes in Indonesia registered in the database repository, inappropriate primer pair selection, low DNA quality, and the absence of target species DNA in collected water samples. The results demonstrated the significance of correctly registering DNA barcodes to the database and appropriate primer pair selection to identify eDNA metabarcoding. This study provides recommendations using eDNA metabarcoding for monitoring in future work.

Broodstock development, induced spawning and larval rearing of the bilih, Mystacoleucus padangensis (Bleeker, 1852), a vulnerable species, and its potential as a new aquaculture candidate

Background: Mystacoleucus padangensis living in Lake Singkarak, Indonesia, has high potential market demand but is threatened by overfishing and has not been successfully cultured. This study describes the first broodstock development, induced breeding, and larval rearing of M. padangensis. Methods: A total of 1,000 female and 1,000 male broodfish were collected from the wild and reared in two concrete ponds (128 m2) at the Centre for Biodiversity Conservation, P.T. Semen Padang, Indonesia. The broodfish were fed commercial feed to satiation at 09:00 and 17:00 h. The females (average weight 7.56 ± 0.85 g) and males (4.86 ± 1.20 g) were selected at a ratio of 1:4 (female:male), and gonad maturation was induced with a single dose of GnRH analogue (Ovaprim) of 0.1 ml/fish. At 16 h after hormone injection, eggs were collected individually into a plastic vessel. Spermatozoa were collected with sterile syringes. Eggs were fertilized using the "dry" method, and 0.5 ml samples (equal to 100 eggs) were taken. The eggs were incubated in a plastic strainer with a water volume of 1.57 litres and placed in a tarpaulin pond with a volume of 150.72 litres. Results: The overall hatching rate was 78.93 ± 4.13%. The newly hatched larvae were 3900.81 µm long, with a yolk sac of 82881.480 µm2. The mouth opened at 72 DPH with a gape measuring approximately 61.880 µm. The protocol of larval feeding started with artificial feed, followed by Artemia nauplii up to 30 DPH. Weaning of larvae started at 4 DPH. Larvae started metamorphosis by 15 DPH and ended by 22 DPH when the larvae reached 7430.27 µm. Larval rearing resulted in an average survival rate of 28.4 ± 3.04%. Conclusions: Its successful spawning induction and high larval hatching and survival rates make M. padangensis an excellent aquaculture candidate.