The study was conducted to establish habitat connectivity of Siganids and Lutjanids along mangrove, seagrass and coral reef ecosystems in the coastal waters of Misamis Occidental. A total of 449 individuals belonging to six species of Siganids and five of Lutjanids were identified from the three different study sites. Three species of Siganids and one species of Lutjanids were found common in all ecosystems. Coral reef ecosystem had higher abundance of siganids and lutjanids compared to mangrove and seagrass ecosystems. Siganus spinus and Siganus guttatus exhibited behavior of being ontogenetic shifters. The juvenile individuals prefer to inhabit mangrove and seagrass ecosystem and migrate to coral reef ecosystem as they become adult. Siganus fuscescens are a generalist species, moving across three ecosystems from early life stage to adult. Lutjanus ehrenbergii is an ontogenetic shifter species: the juveniles prefer to stay in mangrove and seagrass ecosystems and adults migrate to coral reef ecosystem. The distribution of common Siganids and Lutjanids among the three major coastal ecosystems based on their different life stages suggests that these ecosystems are interconnected. Results on gut-content analysis reveal that the major food items of Siganids were seagrasses and seaweeds indicating a general trend of being herbivores while the major food items of Lutjanids were crustaceans, small fishes and cephalopods indicating that they are mainly carnivores. The study provides evidence of connectivity of major coastal ecosystems. Thus, removing one ecosystem will affect the other important ecosystems.
