VOLUME 65 : 2017

The Philippines with 7,641 islands is considered to have one of the most diverse aquatic ecosystem endowed with rich marine flora. This study focused on the assessment of macroalgae in the two islands of Northern Samar, Biri Island and Dalupirit Island, as well as their diversity, abundance and distribution. During collection on July 2016, the complete thalli of live specimens were gathered and their counts and distribution patterns were determined by using 15 quadrats in Dalupirit Island and 26 quadrats in Biri Island. A transect line length of 150 m and 260 m were used, respectively. About 86 macroalgal taxa were gathered and identified for both islands in which 22 out of the 86 taxa were found common to both islands. In Biri Island, 57 taxa were found with 35 being unique to the island. In Dalupirit Island, 51 taxa were identified with 29 being unique to the island. Rhodophyceae showed dominance both in Biri Island and Dalupirit Island having 46% and 43%, respectively, followed by Chlorophyceae with 33% in Biri Island, and 39% in Dalupirit Island, and lastly, Phaeophyceae having 19% for Biri Island and 20% for Dalupirit Island. In terms of percent cover, Phaeophyceae and Chlorophyceae are the most abundant in Biri Island and Dalupirit Island, respectively. Padina japonica is the most evenly distributed in Biri Island while Ulva reticulata is the most evenly distributed in Dalupirit Island.

Keywords: Biri Island, Chlorophyceae, Dalupirit Island, Macroalgae, Phaeophyceae, Rhodophyceae