Conference Proceedings

Hatchery production of sea cucumbers: Status, problems and directions

2025-12-09T06:08:07Z

Hatchery production of sea cucumbers: Status, problems and directions Altamirano, Jon Uy, Wilfredo; Trillo , Jessah ; Sornito, Marnelle B.; Bacsarpa, Charmjill; Carillo, Donn Charles N.; Leopardas, Venus Sea cucumbers are ecologically and economically important marine invertebrates, whose wild populations have been threatened by overfishing in recent decades. The rapid decline in wild stocks was driven by high market prices of sea cucumber products for food and medicine. Fortunately, recent developments in hatchery seed production technologies have paved the way towards establishing a more sustainable sea cucumber industry through aquaculture without dependence on massive collections from natural populations.

Characterization of wild eucheumatoids from Visayas, Philippines as inferred from the mitochondrial cox2-3 spacer sequence

2023-03-22T04:02:00Z

Characterization of wild eucheumatoids from Visayas, Philippines as inferred from the mitochondrial cox2-3 spacer sequence Sibonga, Rema; Brakel, Janina; Gachon, Claire; Faisan, Joseph P., Jr.; Brodie, Juliet; Ward, Georgia; Ferriols, Victor Marco Emmanuel; Luhan, Maria Rovilla; Hurtado, Anicia Q. Ferrer, Alice Joan Eucheumatoids are the major seaweed species cultivated in most coastal areas in the Philippines, being a major source of income for many families. Seaweed farmers face issues such as lack of good quality cultivars and the presence of diseases and epiphytes in the cultivated stocks. This study characterizes the wild eucheumatoids, which are potential sources of cultivars that might be resistant to diseases and epiphytes. Wild eucheumatoids were collected from Iloilo (N=18), Guimaras (N=10), and Bohol (N=20), Philippines. Gross morphology was described, and a 10-mm apical tip was excised for DNA extraction. PCR amplification and sequencing using cox2-3 spacer genetic markers were done. Based on sequence data, 5 species can be identified from the Visayas region: the commercially cultivated Kappaphycus alvarezii (Iloilo, Bohol), K. striatus (Iloilo, Guimaras), and Eucheuma denticulatum (Iloilo, Bohol) and the currently uncultivated K. cottonii (Iloilo) and Kappaphycus sp. (Iloilo, Bohol). Haplotype network analysis identifies individuals of K alvarezii and E. denticulatum as haplotype E3 and E13, respectively, which are haplotypes previously reported from seaweed farms and globally distributed for cultivation purposes. The K. striatus from Iloilo and Guimaras are identified as haplotype E89, and the K. cottonii from Iloilo is haplotype E108 which has been described previously from seaweed farms and wild populations, respectively. Interestingly, Kappaphycus sp. from Iloilo and Bohol are identified as haplotype GUI1 initially described in 2014 and yet to be identified up to the species level. Our study shows that purely morphological identification is not sufficient to reliably identify species, thus highlighting the need to employ molecular techniques supporting strain selection. In summary, it reveals a rich diversity of wild eucheumatoids in the Visayas region of the Philippines. In-vitro studies need to reveal the performance of individuals from these wild populations but highlight a great potential for the development of new cultivars.

Improving artisanal fisheries through community-based prawn stock enhancement in a mangrove estuary

2023-03-13T01:23:48Z

Improving artisanal fisheries through community-based prawn stock enhancement in a mangrove estuary Altamirano, Jon Tropical seafood, especially prawns, have always been in high demand with high market prices. Because of this, wild prawn resources are often overfished as indicated by the increasing number of fishers, but with overall declining catch volume and sizes through the years. Prawn aquaculture has, as of course, significantly contributed to the total yield in the past decades. However, the expansion of farms and ponds has often negatively affected the natural nursery grounds in the estuaries and mangroves. The economic gains from aquaculture are limited only to those who invested. However, local communities and artisanal fishers are often deprived of such gains. They are still reliant upon the dwindling natural stocks of fisheries resources. This is where the concept of stock enhancement comes in, wherein hatchery-produced juveniles are released into the water body in order to increase capture fisheries yield for local fishers. In this talk, I will present the case of the tiger prawn Penaeus monodon stock enhancement in the New Washington Estuary (NWE), in Aklan, central Philippines. The NWE was a productive fishing ground providing >24 kg/gear/day of catch in the 1970s but steadily declined to <0.7 kg/gear/day in 2010s. Prawn catches declined both in quality and quantity. Meanwhile, mangrove cover was reduced from 4800 ha in 1950s to only <800 ha in 2010s. Site-specific studies were conducted in NWE on prawn nursery rearing, small-scale release and monitoring experiments, as well as social assessments. Our studies produced essential scientific data to guide future stock enhancement activities in NWE. Even at an experimental scale, our releases showed significant increases in catch by at least 8% but can potentially increase daily income by >400%. However, in order to sustain the prawn fisheries and optimize the benefits, long-term management plans by all stakeholders are needed, especially between the communities and the local government.

Burning grey: The worldwide influence of a locally published grey literature

2023-01-26T07:10:30Z

Burning grey: The worldwide influence of a locally published grey literature Palcullo, Vince Ervin; Rivera, Donna May C.; Dumenden, Via Marie F.; Peleña, Ma Cynthia Tolones; Geromiano, Joy F.; Superio, Daryl Rice is a major staple crop in the Philippines, which produces a large amount of rice each year. On the other hand, rice production generates biomass waste in the form of rice husks. In consideration of the rice husks’ potential as a biomass energy source and support the development of the rice husk gas stove technology in the Philippines, Engineer Alexis T. Belonio had published a grey literature (GL) entitled “Rice Husk Gas Stove Handbook.” Hence, to fully understand the impact of the technology, a citation analysis was conducted. The works that cited the GL were retrieved from Google Scholar using Harzing’s Publish or Perish software. The complete title of the GL was used as keywords for the search string. Results revealed that the GL was cited by 155 literatures written by 398 authors from 31 countries. Seventy-five (48.4%) of the 155 literatures were cited 797 times. The results showed the wide utilization and the impact of locally-published GL, thereby confirming GL’s value in research and development.