Ecosystem is the basic ecological unit of study. It is made up of the living and the non-living components. The mangrove ecosystem is an example of a natural ecosystem consisting the structural and functional components. The mangrove ecosystems of the Philippines, such as those found in the island province of Catanduanes in Bicol are characterized by different features and have benefits to the local people both at the ecological and economic standpoints. The mangrove floras of this province consist of 13 species of major mangrove flora represented by the 5 families of vascular plants: Avicenniacea, Combretaceae, Palmae, Rhizophoraceae and Sonneratiaceae. There are 10 minor species and 14 associated mangrove species found in the mangrove areas of the province.