Undergraduate Special Problem
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/30
Browse
Search Results
Now showing 1 - 4 of 4
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 A study of the gut contents of compressed tubby (Canthigaster compressa) from Talibon, Bohol and Palompon, Leyte, PhilippinesCaduada, Laymart A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2017-06)The Philippines has one of the longest coastlines and is among the top producers of fisheries products in the world. The industry however is threatened by unsustainable fishing practices and dwindling resources. Proper fisheries management is hindered by an extensive lack of biological information on resource populations. Studying fish feeding habits based on gut content analysis could provide insights on fish feeding patterns and trophic interactions in aquatic food webs and enhance our understanding of exploited resources. The study compares the composition of the gut contents of Canthigaster compressa caught by sled trawl in seagrass beds in Talibon, Bohol and Palompon, Leyte. Sixty eight specimens from Talibon and 80 from Palompon were examined. Chyme made up 70-76% of the total gut contents in both areas. A total of 23 prey items were observed. Diet composition in Palompon was more diverse as compared to Talibon. Gut contents changed with size/age, with an apparent increase in the proportion of seagrass/algae as fish size increased. This suggests that the tubby shifts to a more herbivorous diet as they grow older. The amount of forams in the guts also decreased with size which could be attributed to a shift in habitat from seagrass to coral reefs. The results also show that crustaceans are more abundant in Palompon than in Talibon which could mean that Palompon has a richer seagrass-associated crustacean population. Further studies about the abundance of crustaceans in the fish diet in Palompon and Talibon is encouraged as it could be useful in assessing the ecological conditions of the areas.Item Temporal variation in the subtidal macroinfaunal composition of a NaGISA seagrass bed in southern Guimaras, Philippines between 2015 and 2016Bacabac, Earl Jeroh I. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)Seagrass meadows are amongst the most abundant and diverse ecosystems when it comes to biodiversity but due to stress induced by natural and anthropogenic factors, a worldwide decline threatens the vital ecological functions of these habitats. Studying the infauna provides clues and information about the complexity of seagrass ecosystems and provides information that would facilitate better seagrass area management and associated conservation efforts. The NaGISA sampling protocol was conducted in Calaparan seagrass bed in TINMAR, Guimaras, Philippines between Sept. 2015 and 2016. Overall macrofaunal density was recorded at 21,954.80 ± 36,109.62 ind.m'2 with macrofaunal density higher in 2015 than in 2016 albeit, insignificant except for capitellid polychaetes. Community structure analysis also found similarity in dominance patterns in the subtidal zone with other soft-bottom macrofaunal studies in the Philippines with polychaetes, nematodes, and crustaceans as the respective dominant macrofaunal groups observed. Dominant polychaete families were also found to be cosmopolitan and opportunistic. Granulometric analysis characterized the sediment as pebble to medium sand with mid phi values ranging from -3.69 to 1.10 but poor sorting in all sampling points was observed. Cymodoceaceans dominated the subtidal zone in both years (Halodule pinnifolia in 2015; Cymodocea rotundata in 2016). Correlation analysis showed macrofaunal densities to have a significantly strong negative relationship with sorting index and percent gravel while a strong positive relationship with percent seagrass cover. The poor sediment sorting, coarse sediment character, and seagrass cover were the primary factors influencing the observed decrease in macrofaunal density but the decrease is considered normal for the variability of macrofauna in the area. A clearer picture of macrofaunal interactions would be provided with comparison to intertidal macrofauna of the area in the sampling years and data on additional factors that were not measured in the study.Item Spatial variations of Benthic meiofauna communities from Palompon Bay, Northern LeyteBalasa, Melvy June (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2013-04)Meiofauna play a significant role in maintaining ecological balance in marine ecosystems especially in the dynamics of the seagrass meadows. The meiofauna links the upper trophic level with detritus-feeding organisms. Only few studies have been conducted in the Philippines, while no studies have been. This study was conducted in Palompon, northern Leyte in November 2011, to determine the spatial distribution of meiobenthic fauna in the area and to compare community structure in terms of species composition, species density, and species diversity among five stations included in the survey. Twenty taxa were identified with nematodes being numerically dominant, followed by harpacticoid copepods. It also showed the highest mean abundance for the entire habitat type. The overall mean density was 194585.1528 ind. m2, with the highest population at station 4. And the lowest population was recorded at station 2. Soft bottom habitat showed the highest recorded mean density among the 5 stations, Harpacticoids mostly dominated sandy substrate while nematodes were widely distributed.
