This project will be implemented to develop a database on the species biodiversity, and to assess and monitor the ecological status of nine nonwadeable rivers within the Samar Island Natural Park (SINP), namely: Catarman, Catubig, and Pambujan rivers in Northern Samar; Calbiga, Gandara, and Golden rivers in Western Samar; and Can-avid Oras, Suribao, and Taft rivers in Eastern Samar. These rivers are important biodiversity and tourism hotspots in region 8, and vital links in the park’s ecological processes. They have been sites of rapacious exploitation, such as mining, logging and damming- activities believed to be the primary causes of recurring and localized catastrophic flashfloods and landslides in Samar. Biodiversity assessments and monitoring will be conducted for two years to generate data on riverine biodiversity, ecological health and integrity status. Specifically, inventory and species profiling of riverine and riparian megafauna, macroflora and macrofauna will be conducted, and the ecological integrity and carrying capacity of rivers will be assessed and monitored based on water quality parameters, biological indicators, multimetric indices, and indices of biotic integrity. The data generated will be used as significant inputs in the formulation of sustainable utilization, and pro-poor and gender responsive protection and management policies of the SINP, consistent with the goals, guidelines, and definition of a natural park according to the International Union for the Conservation of Nature (IUCN). The data will also serve as reference information for monitoring and future assessments of the river ecosystems’ responses to current protection and management initiatives