http://hdl.handle.net/20.500.14277/15 These papers were contributed by SEAFDEC/IFRDMD staff to various national and international journals 2026-04-28T10:28:58Z http://hdl.handle.net/20.500.14277/124 High genetic diversity in anguillid glass eels across three Southeast Asian countries revealed through mitochondrial DNA D-loop sequences, with notes on population structure Marini, Melfa; Pedrosa-Gerasmio, Ivane R.; Santos, Mudjekeewis D.; Romana-Eguia, Maria Rowena R.; Nguyen, Binh Thanh; Shibuno, Takuro Understanding the genetic diversity and population structure of anguillid eels is crucial for effective management. In this study, we used the mitochondrial DNA (mtDNA) D-loop marker to identify anguillid glass eels and assessed their genetic diversity across six sampling sites spanning three Southeast Asian countries. We also examined the population structures of Anguilla marmorata and A. celebesensis. We validated nine distinct species and subspecies of anguillid eels from 465 specimens collected in Indonesia (n = 246), the Philippines (n = 119), and Vietnam (n = 100). High gene diversities were observed across the species, ranging from 0.979 (A. celebesensis) to 1.000 (A. bicolor bicolor, A. marmorata, and A. interioris). Correspondingly, nucleotide diversity values were relatively low, varying from 0.036 (A. marmorata) to 0.057 (A. interioris). A. marmorata (n = 162) displayed a broad distribution, being observed across all six sites, with a significant yet low average fixation index of 0.05755. Pairwise comparisons of FST values between Cimandiri and other locations (except for Cagayan) were relatively high and statistically significant (p < 0.01), indicating significant genetic differentiation of Cimandiri samples compared to most locations in this study. On the other hand, A. celebesensis (n = 110), exhibited a non-significant and low fixation index (0.007), indicating no genetic differentiation in samples from Poso and Poigar Rivers, Indonesia. Our findings highlight the essential need for coordinated management strategies among regions that share common stocks. Additionally, this study underscores the efficacy of the mtDNA D-loop in precisely identifying glass eel species/subspecies and elucidating the genetic diversity and population structure of tropical anguillid eels. 2024-09-01T00:00:00Z http://hdl.handle.net/20.500.14277/109 Assessing the ecosystem approach to fisheries management in Indonesian inland fisheries Ditya, Yoga Candra; Muthmainnah, Dina; Wiadnyana, Ngurah Nyoman; Makmur, Safran; Kaban, Siswanta; Makmur, Hukmanan Rais; Hidayah, Taufiq; Anggraeni, Dian Pamularsih; Antoni, Rezki; Dwirastina, Mirna; Koeshendrajana, Sonny Inland waters provide huge fish resources and are exploited as food security by local people. The method used in this study was intended to evaluate the performance of the management in terms of the Ecosystem Approach to Fisheries Management (EAFM). The study was conducted in five districts in Indonesia, namely Cilacap, Sukabumi, Kampar, Kapuas, and South Barito, from February to August 2019. The primary data were gathered through observation and interviews with fishers, local government, indigenous community, NGO, and other stakeholders. The secondary data were collected from previous studies. The EAFM domains are presented in a questionnaire that refers to the technical guidelines for assessing fisheries management indicators with an ecosystem approach. The indicators are grouped into seven domains in rating the current management of inland fisheries. The Likert score is used to measure respondents’ attitudes to a particular question or statement. The score criteria used in examining fishery management by EAFM tools-based ordinal 1,2,3, designed to measure opinion or perception from the questionnaires. The results showed that the economy and stakeholder domain were poor categories, indicated by a red flag. Nevertheless, the management conditions, especially for the managed fish resources domain, were classified as good. 2021-12-01T00:00:00Z http://hdl.handle.net/20.500.14277/108 Assessing temporal patterns and species composition of glass eel (Anguila spp.) cohorts in Sumatra and Java using DNA barcodes Wibowo, Arif; Hubert, Nicolas; Dahruddin, Hadi; Steinke, Dirk; Suhaimi, Rezki Antoni; Samuel; Atminarso, Dwi; Anggraeni, Dian Pamularsih; Trismawanti, Ike; Baumgartner, Lee; Ning, Nathan Anguillid eels are widely acknowledged for their ecological and socio-economic value in many countries. Yet, knowledge regarding their biodiversity, distribution and abundance remains superficial—particularly in tropical countries such as Indonesia, where demand for anguillid eels is steadily increasing along with the threat imposed by river infrastructure developments. We investigated the diversity of anguillid eels on the western Indonesian islands of Sumatra and Java using automated molecular classification and genetic species delimitation methods to explore temporal patterns of glass eel cohorts entering inland waters. A total of 278 glass eels were collected from monthly samplings along the west coast of Sumatra and the south coast of Java between March 2017 and February 2018. An automated, DNA-based glass eel identification was performed using a DNA barcode reference library consisting of 64 newly generated DNA barcodes and 117 DNA barcodes retrieved from BOLD for all nine Anguilla species known to occur in Indonesia. Species delimitation methods converged in delineating eight Molecular Operational Taxonomic Units (MOTUs), with A. nebolusa and A. bengalensis being undistinguishable by DNA barcodes. A total of four MOTUs were detected within the glass eel samples, corresponding to Anguilla bicolor, A. interioris, A. marmorata, and A. nebulosa/A. bengalensis. Monthly captures indicated that glass eel recruitment peaks in June, during the onset of the dry season, and that A. bicolor is the most prevalent species. Comparing indices of mitochondrial genetic diversity between yellow/silver eels, originating from several sites across the species range distribution, and glass eels, collected in West Sumatra and Java, indicated a marked difference. Glass eels displayed a much lower diversity than yellow/silver eels. Implications for the management of glass eel fisheries and species conservation are discussed. 2021-04-29T00:00:00Z http://hdl.handle.net/20.500.14277/64 Abundance and composition of phytoplankton communities in middle stream of Citanduy river, West Java Sawestri, Sevi; Rais, Aroef Hukmanan The relationship between phytoplankton composition and environmental conditions in their habitat provides an important role for their as an assessment of the status and quality of river waters and the management of these waters. The aim of this research was studied of composition and abundance of phytoplankton communities in Citanduy River, particularly in middle stream. The study has conducted in April, July, and October 2018. The study location consists of 4 stations. The research has measured the abundance index, diversity index, and dominance index of plankton. The physic-chemical waters parameters which was measured consist of temperature, pH, DO, depth, transparency, nitrite, ammoniac, nitrate, total phosphate, and chlorophyll-a. Phytoplankton of Citanduy River consists of 4 classes. The abundance index of phytoplankton was around 2,578-7,366 cells/L; diversity index of phytoplankton is around 0.48-2.57, while the highest dominance index was Pediastrum sp with 0.56. Based on multiple regression analysis, the abundance of phytoplankton in April was influenced by nitrates and temperature. The abundance of phytoplankton in July is influenced by nitrite and ammonia. Meanwhile, in October, phosphate and oxygen parameters affect the abundance of phytoplankton. The Citanduy River is still in the stable category because the water quality is still in a sufficient condition for aquatic biota, especially phytoplankton. The ammonium and total phosphate of BBWS station in October were higher than standard. The high concentration of nitrogen and phosphorus nutrients is the results from the surrounding land for rice fields, plantations, fish farming, and waste disposal. 2021-01-01T00:00:00Z