Community Structure of Herbivore Reef Fishes in Lagonoy Gulf, Eastern Philippines

Abstract

Reef herbivory is a critical ecological process that can control community structure in a reef and can determine recovery potential; therefore, herbivores are an important input in coral reef resiliency.  In Lagonoy Gulf, herbivorous reef fishes were surveyed from 22 sampling stations with 93 transects of which 149 species belonging to 14 families were recorded. Although no differences between stations were detected among their biomasses, sizes, abundance and number of species; clustering of stations showed significant differences between clusters. Functional grouping suggests that almost all reefs experienced overfishing as average biomasses were relatively low, with grazers weighing only 112 kg ha^-1, scrapers with 56 kg ha^-1, browsers 14 kg ha^-1, and territorial damselfish 70 kg ha^-1.  Marine Protected Areas (MPA) were noted to have no impact on reefs’ herbivore community structure since it was almost similar with outside-MPAs and non-MPAs, but then, MPAs have higher overall values than the two other areas. Generally, presence of herbivore fishes in Lagonoy Gulf is a good indicator of the reef’s potential recovery before and after a disturbance event.  Furthermore, the diverse herbivore population of the Gulf enhances functional redundancy.