Inventory of fish fauna in Siargao Island Protected Landscape and Seascape, Surigao del Norte, Philippines

Abstract

Siargao Island Protected Landscape and Seascape (SIPLAS) has an extensive mangrove area that supports marine biodiversity. This study documented mangrove fishes in three selected sites using a fishery-dependent survey approach, with samples taken by commissioned fishing or landed catch by local fishermen. A total of 129 species belonging to 38 families were documented and identified in the study. Dapa had the highest species richness with 70 species (54.26%), followed by Santa Monica with 63 species (48.84%), and San Benito with 28 species (21.71%). Eighty-four species (65.11%) were recorded as 'target' or economically significant, 39 (30.23%) were 'major species' or fishes that are not commercially valuable, while six (4.65%) were identified as 'indicator species' or species with ecological importance. The high fish species richness recorded for commercially important families, i.e., Haemulidae, Acanthuridae, Serranidae, Lethrinidae, Lutjanidae, and other target species indicate mangrove resilience to support these species. Six species (Balistoides viridescens, Chaetodon auriga, Chaetodon kleinii, Chaetodon lunulatus, Chaetodon octofasciatus, and Chaetodon ulietensis) were identified as ecologically important and native in the area. Juvenile fishes of coral reef species were recorded, such as Naso spp., C. auriga, Hemigymnus melapterus, Arothron spp., Naso vlamingi, Hemigymnus melapterus and Scolopsis margaritifera. Apart from these juveniles, the rest of the species observed are usually found on coral reefs, such as commercially significant threadfins, trevallies, queenfish, snappers, and groupers, which are all considered major migratory species. Findings of this study will undoubtedly supplement important data of SIPLAS for more conservation efforts (e.g. designation as Ramsar Site).