Undergraduate Special Problem
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/30
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Item Rock-associated Cryptofauna in Seagrass Beds in Taklong Island National Marine Reserve, Guimaras, PhilippinesCamache, Christian M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)It has been suggested that cryptofauna makes up the bulk of marine ecosystems. Little is known of the ecology of cryptofauna and the few studies conducted about them stress their importance in the ecology of marine systems. This study was conducted to assess the biodiversity of rock-associated cryptofauna in seagrass beds in the Taklong Island National Marine Reserve (TINMR) and to correlate their abundance and diversity to the rugosity of the substrate. Rock samples were collected from three seagrass beds, namely: Calaparan, Kalirohan, and Bagatnan. The cryptofauna inhabiting the rock samples were extracted using forceps and were then sorted into major taxonomic groups and identified. The density of each taxonomic group, the diversity and similarity indices of and among sites, and the rugosity and volume of the rock samples were calculated. A total of 2,255 individuals were collected belonging to 97 OTUs and eight major taxonomic groups, with a mean density of 1.13±0.51 indiv/mL. Foraminiferans and crustaceans were the most prominent organisms observed in all sites while polychaetes showed significant density variations. Cryptic fauna diversity was low in all sites. Kalirohan had the highest diversity index (H’ = 0.86 ± 0.119) while Calaparan had the lowest (H’ = 0.67 ± 0.125). All sites showed low similarity coefficients with Kalirohan and Bagatnan showing the highest value (31% similarity). No significant correlation was found between the rugosity of rock substrates and density of cryptofauna contrary to expected trend. This suggests that rugosity may not be a key determinant of cryptofaunal abundance and diversity in rock substrates in these seagrass beds.Item Epibiota of Holothuria scabra (Jaeger, 1833) from TINMAR, Southern Guimaras and Sagay Marine Reserve, Negros OccidentalCalizar, Jessica Joyce D. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2013-04)The composition and abundance of epibiota on the sea cucumber Holothuria scabra collected in TINMAR, Southern Guimaras (Panay Gulf, northern Sulu Sea) and Sagay Marine Reserve, Negros Occidental (Visayan Sea), were determined. Epibiotic organisms on 10 Holothuria scabra individuals in each site were detached from the body surface with a fine brush dipped in alcohol. Samples collected were fixed in buffered formalin, followed by counting and identification under light microscopy. Sea cucumber epibionts consisted of photosynthetic protists, mainly diatoms (Phylum/Division Bacillariophyta), and small marine invertebrates (Protozoa, Mollusca, Arthropoda, and Annelida). Some 2,237 epibionts were counted with the diatoms as the most abundant and frequently encountered group. Epibiont species on Holothuria scabra were almost the same in both sites, except for annelids which was only encountered in samples from Sagay. Mean epibiotic abundance of Holothuria scabra from TINMAR was 61 per individual which was about a third of epibiotic abundance on individuals from Sagay (163 per individual). This study provides preliminary information on epibionts present on Philippine holothurians, and will help future researches in this field.Item Community structure of holothuroids in selected seagrass beds in Taklong Island National Marine Reserve, Guimaras, PhilippinesCalaguing, Aldwyn C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Sea cucumbers are beneficial to mankind commercially as food and medicinal commodity. Overexploitation and illegal catch of these organisms even within Marine Protected Areas (MPAs) caused stock depleting and even local extinction of some populations in the country. Monitoring and regular assessment of their population is a must for their proper management and protection. This study investigated the status of holothuroid community within 4 selected seagrass meadows in Taklong Island National Marine Reserve (TINMR), Nueva Valencia, Guimaras. Holothuroid composition and estimates of density, frequency and distribution were determined through plot method. Species identification was based on gross morphology and spicule analysis. There were 40 individuals collected identified as 5 species, namely, Holothuria atra (n = 18), Holothuria pulla (n = 1), Holothuria scabra (n = 5), Bohadschia vitiensis (n = 2) and Synapta maculata (n = 13). The first 4 belonged to Order Aspidochirotida and the last belonged to Order Apodida. Their distribution and community structure in TINMR are likely influenced by the physical and chemical environment, seagrass community poaching, and cryptic behavior.Item Oxygen requirement of Sea Cucumber (Bohadschia marmorata)Cahuya, Jezyl Leigh D. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2017-06)The oxygen consumption of juvenile sea cucumber Bohadschia marmorata was studied in the laboratory. The effects of temperature and body weight on oxygen consumption rate (OCR) were determined by measuring the dissolved oxygen levels using closed bottle respiratory method. Mean weight specific OCR of B. marmorata juveniles was low (9±4 pgO2h-1g-1). The OCR decreased with time from 16.9±9.1 to 6.09±3.86 ugO2h-1g-1 rapidly declining in the first two hours then, more gradually thereafter (R2=-0.92). Factors such as temperature and size affect OCR. Oxygen consumption rate tends to increase with increasing temperature. Bigger animals have low OCR levels than smaller ones (R2=0.32).Item Zooplankton composition, abundance and diversity in selected Municipalities of Negros Occidental and AklanAusan, Aisa Marie U. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)Zooplankton samples were collected last May and June 2014 from 20 stations in the vicinity of Kalibo, Aklan and Pontevedra, San Enrique, and Valladolid, Negros Occidental. Three hundred fifty-three (353) liters of water were filtered per station thru a 5m vertical haul of plankton net with a diameter of 30cm and a mesh size of 20μm. Overall zooplankton densities were higher in Negros Occidental, specifically in Valladolid (D=1915.3 cells/L), than in Kalibo, Aklan (D=7.2 cells/L). On the other hand, zooplankton community was most diverse in Kalibo (H’ = 2.6) compared to Valladolid (H’=1.3), San Enrique (H’=2.1) and Pontevedra (H’=1.8). Jaccard’s similarity index was highest between Pontevedra and San Enrique while lowest between Valladolid and Kalibo. In Kalibo there were four major groups of zooplankton. Most dense of these were the tintinnids (3.9 cells/L) followed by copepods (2.5 cells/L), molluscs (7xlOE-lcells/L) and polychaetes (IxlOE-lcell/L). Among the copepods Subeucalanus was the most abundant zooplankton genus. In Pontevedra and San Enrique, Negros Occidental, copepods were the most abundant group with a mean density of 205.3 cells/L and 312.1 cells/L, respectively. The relative abundance ofAcartia (36.5%) and Longipedia (22.6%) made them the dominant zooplankton genera in Pontevedra and San Enrique, respectively. Like in Kalibo, the tintinnids were also the most abundant group in Valladolid (1879.2 cells/L). Copepods followed with a mean density of 35.7 cells/L, while Polychaetes comprised only 4xlOE-l cells/L. Epiplocylis was the most abundant tintinnid in Valladolid while Xystonella in Kalibo. Varying sampling time within months and day is the possible cause of the differences in zooplankton abundance, composition, and diversity since some zooplankton species undergo diel vertical migration.
