National Committee on Marine Sciences (NCMS)
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- Restriction site-associated DNA sequencing reveals local adaptation despite high levels of gene flow in Sardinella lemuru (Bleeker, 1853) along the northern coast of Mindanao, PhilippinesLabrador, Kevin; Palermo, Joseph Dominic; Agmata, Altair; Ravago-Gotanco, Rachel; Pante, Ma. Josefa (Frontiers Media SA, 2022-02-24)Stock identification and delineation are important in the management and conservation of marine resources. These were highlighted as priority research areas for Bali sardinella (Sardinella lemuru) which is among the most commercially important fishery resources in the Philippines. Previous studies have already assessed the stocks of S. lemuru between Northern Mindanao Region (NMR) and Northern Zamboanga Peninsula (NZP), yielding conflicting results. Phenotypic variation suggests distinct stocks between the two regions, while mitochondrial DNA did not detect evidence of genetic differentiation for this high gene flow species. This paper tested the hypothesis of regional structuring using genome-wide single nucleotide polymorphisms (SNPs) acquired through restriction site-associated DNA sequencing (RADseq). We examined patterns of population genomic structure using a full panel of 3,573 loci, which was then partitioned into a neutral panel of 3,348 loci and an outlier panel of 31 loci. Similar inferences were obtained from the full and neutral panels, which were contrary to the inferences from the outlier panel. While the full and neutral panels suggested a panmictic population (global FST ∼ 0, p > 0.05), the outlier panel revealed genetic differentiation between the two regions (global FST = 0.161, p = 0.001; FCT = 0.263, p < 0.05). This indicated that while gene flow is apparent, selective forces due to environmental heterogeneity between the two regions play a role in maintaining adaptive variation. Annotation of the outlier loci returned five genes that were mostly involved in organismal development. Meanwhile, three unannotated loci had allele frequencies that correlated with sea surface temperature. Overall, our results provided support for local adaptation despite high levels of gene flow in S. lemuru. Management therefore should not only focus on demographic parameters (e.g., stock size and catch volume), but also consider the preservation of adaptive variation.We would like to acknowledge the assistance provided by Ma. Rio Naguit, Asuncion De Guzman, Jerry Garcia, Jhunrey Follante, Joshep Mercene, and John Christopher Azcarraga in sample collection and initial processing. We also acknowledge the research staff of the Marine Molecular Ecology and Evolution Laboratory (MMEEL), as well as the Marine Genomics and Molecular Genetics Laboratory (MGMGL) and its head, Arturo Lluisma, for providing valuable input in the conduct of the experiment and analysis of the data. Finally, we extend our gratitude to Demian Willette, Laura David, and Jonas Quilang for their valuable feedback on the manuscript.
- Genetic diversity and population connectivity of the greenblotch parrotfish (Scarus quoyi Valenciennes, 1840) within southern Mindanao inferred from mitochondrial 16S rRNALabrador, Kevin; Fortaleza, Maybelle; Cabasan, Joey; Elumba, Merlene; Nañola, Cleto (Science and Technology Information Institute, 2022-10-03)A genetic assessment was done on the greenblotch parrotfish (Scarus quoyi Valenciennes, 1840) in three bays within southern Mindanao, Philippines. Mitochondrial 16S rRNA recovered 12 haplotypes, one of which was dominant in all sites. Despite the reported phenotypic variation from previous assessments, there was neither evidence of genetic structure (global Φst = 0.012, p = 0.13) nor isolation by distance (r = 0.05, p = 0.50). Genetic diversity was also low (Hglobal = 0.472; πglobal = 0.13%), with ~ 77% of haplotype diversity accounted for with just 69 samples. While connectivity suggests continuous larval exchange within southern Mindanao owing to the species’ high dispersal potential, low genetic diversity implies reduced effective population size, probably due to recent bottlenecks (e.g. overfishing, habitat destruction). Although this study provides baseline genetic information on the local population, inferences are considerably limited by the genetic marker used and the spatial scale under investigation. A thorough understanding of the population will be possible if the entire habitat range of the species is assessed using markers with high resolving power, such as the hypervariable mitochondrial control region, microsatellites, or genome-wide single nucleotide polymorphisms (SNPs).This project was funded by the DOST-PCAARRD (Department of Science and Technology–Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development) through the projects titled “DNA Barcoding and Genetic Diversity of Selected Marine Fishes along the North Bifurcation of the North Equatorial Current (NEC)” and “DNA Barcoding of Selected Marine Fishes in Davao and Sulu Archipelago (MINDA).” Sample collection was covered by the DARETO (Discovery-Applied Research and Extension for Trans/Inter-disciplinary Opportunities) research grant under CHED (Commission on Higher Education) through the project entitled “Bioeconomic Assessment and Modelling of Reef Fisheries and Sustainable Harvest Project”. We would like to thank Junissa M. Consuegra, Joemarie J. Lanutan, and Jodi Eugenia Lourdes F. del Fierro for their assistance in sample collection and laboratory work.
- Shellfish ban up in 10 VisMin areasCariaso, Bella (Philippine Star Printing Co., Inc., 2024-10-01)Ten bodies of water in the Visayas and Mindanao remain affected by the paralytic shellfish poison or red tide toxin, according to the Bureau of Fisheries and Aquatic Resources. The BFAR said a shellfish ban has been imposed on Carigara Bay in Leyte
- Saving the mysterious sea cowsMayuga, Jonathan (Philippine Business Daily Mirror Publishing, Inc., 2022-04-24)Known locally as “dugong” (Dugong dugon), this sea cow is a large, charismatic and gentle creature of the sea that is rarely seen nowadays in coastal and marine areas where they used to thrive. Shy as it is, very little is known about this very elusive marine mammal—its population and distribution, how and where it breeds or congregates, or where and how it raise its young. Fortunately, as a species, dugong is surviving the numerous human-induced threats, unlike its cousin, the Steller’s sea cow that lived off the coast of western North America, which became extinct in the 18th century mainly due to hunting.
- Samal dive fest: exploring Samal Island’s diving sites(Sun • Star Publishing, 2022-06-02)The first Samal Dive Festival's fun diving activity proved to be success with around 70 scuba divers, both local and foreign dive enthusiasts from Manila and other parts of Mindanao, participating in the event last May 28 to 29, 2022. The divers, with licenses ranging from open water certification, advanced open water divers, dive masters, and rescue divers, explored Samal Island's emerging dive sites, such as Marissa 3 and Captains One Way, on the first day of the festival. They were also introduced to new dive sites, including Ligid Dako and Aundanao on the second day.
- SEAFDEC backs PH gov't bid to put up feed mill plants(Metropolitan Global PH Communications Co., 2023-01-29)SEAFDEC/AQD has pledged its support to the Bureau of Fisheries and Aquatic Resources (BFAR) to construct commercial-scale aquaculture feed mills for cost-effective feed in strategic locations throughout Panay Island, as well as Luzon and Mindanao in the Philippines. “Development of aquaculture feed mill plants is one of BFAR’s approved projects and is set for implementation this year,” according to BFAR-6 director Remia Aparri. The project is under the National Fisheries Program. BFAR tapped the research center’s technical expertise, particularly on site selection, during a meeting between SEAFDEC/AQD and BFAR on 10 Jan. 2023. Chief Dan Baliao, Dr. Roger Edward Mamauag, SEAFDEC/AQD Feasibility Study team, Aparri, and BFAR-6 staff were present.