Assessment of the Diversity of Macrofauna of Govantes River in Vigan City, Ilocos Sur, Philippines

Macrofauna play a key role in the functioning of riverine ecosystems. However, knowledge about the diversity and functional structure of freshwater   macrofauna   is limited. This study assessed the macrofauna of Govantes River in Vigan City, to identify   the observed species using morphological evidences, and to investigate its abundance and composition, and species diversity. A total of 20 species of macrofauna were found and identified within the Fish Aggregating Device (FAD) in the different stations. These species belong to Ichthyo Fauna (13 species), Crustacea (6 species), and Gastropods (1 species). All the diversity indices H’, J’ and exp (H’) and Ho corresponding to diversity, evenness and richness respectively, are all statistically the same.  This result implies that all the sampling stations have the same diversity, evenness and richness, based on the observed number of individuals of the species found. The dominant species found was Karalla daura in Station 1.

Keywords: abundance, evenness, dominance, ichthyo fauna, crustacea, gastropods