Ecology, Environment and Conservation Paper

PLANKTON ABUNDANCE IN TICAO PASS, MASBATE, PHILIPPINES

Hilconida P. Calumpong, Persie Mark Sienes, Tina Rey Santos,Jose Isidro Michael Padin and Edna R. Sabater

Abstract

Ticao Pass is a narrow waterway located in-between Ticao Island and Sorsogon in the Bicol region of the Philippines. It is known for the presence of whale shark and manta ray aggregations as well as a source of sardines from March to May. These organisms are known to feed on plankton and their presence may be related to plankton abundance indicating Ticao Pass as a potential foraging and nursery area. This study aims at describing trends of plankton composition and abundance in Ticao Pass from September 2010 to April 2011. Six sampling stations were randomly selected along Ticao Pass with three replicates per station using the vertical tow sampling technique. Results showed highest plankton abundance in the month of March 2011 with a mean of 122,954 individuals m-3 + 31,498 (S.D.) coinciding with reported peaks of whale shark aggregation in the area. Dominant plankton groups include Trichodesmium and Chaetoceros for phytoplankton, Ceratium for dinoflagellates, and nauplii and copepods for the zooplankton. Comparing phytoplankton abundance across months indicated a shift in dominance from blue-green algae during the wet season to diatoms in the dry season. An alternating pattern of increase and decrease in phytoplankton with a corresponding similar pattern in zooplankton lagging behind was observed showing a typical predator-prey relationship.