00000ctmaa22000003a 4500 UP-1685675941123958199 Buklod 20180816145801.0 aa rb |||1 u| ta 180816s xx d r |||| u| (iLib)UPTAC-00019010319 UPVTC eng LG 993.5 2018 B5 O45 Olimberio, Roselle B. Comparison of microplastics in the gastrointestinal tract of the detritivore Valamugil speigleri (Bleeker, 1858) and the herbivore Siganus canaliculatus (Park, 1797) from Cancabato Bay, Tacloban City, Philippines. Roselle B. Olimberio 2018 vii, 36 leaves illustrations. A research paper (B.S. Biology) -- University of the Philippines, Tacloban. Microplastics are plastic particles within the size range of 1 nm to <5 mm. Microplastic ingestion has been recorded in a wide variety of marine biota resulting in physiological disorders. This study documents the amount of microplastics in the guts of fish according to their feeding behavior and presumably specific habitats where they are caught in the bay. Seventy gastrointestinal tracts of mullets (Valamugil speigleri) and another 70 from rabbitfishes (Siganus canaliculatus) collected from Cancabato Bay, Tacloban City, Philippines were dissected. The entire digestive tracts (esophagus, stomach, intestines) of each fish were removed, dissolved and filtered. The total number of microplastics observed under stereomicroscope were tallied. There were 41 individuals of S. canaliculatus (n=70) that had ingested microplastics, while 21 individuals (n=70) of V. speigleri contained the said particles. The Pearson correlation value for S. canaliculatus was r=0.04, while V. speigleri was r=0.08. The values were close to zero, signifying a weak correlation between the weight of fish and amount of microplastics found in the GI tract of each individual in S. canaliculatus, as well as in V. speigleri. In terms of microplastics per fish, siganids had a mean +/- sd of 1.21 +/- 1.61 and mullets had 0.47 +/- 0.90. Rabbitfishes, which are herbivores, ingest large amounts of plastics debris than mullets, which mainly feed on detritus. The rabbitfishes probably got the plastic particles from surfaces of seagrasses and microalgae they feed on. While the mullets would have sourced these particles from the detrital matter. Although observed in both species, the more common type of icroplastic observed were fibers rather than fragments. Possible source of these include clothings which release microfibers after washing. Seventy-one percent of the microplastics fibers were documented from S. canaliculatus, while the remaining 29% were fragments. On the other hand, 64% fibers and 36% fragments were retrieved from V. speigleri. Cabansag, Jerome Benedict P. adviser. FI UP UPTAC UPTAC LG 993.5 2018 B5 O45 Thesis