The main means of livelihood of the people is farming and fishing. The municipality's marine environment is home to various species of marine wildlife and plants, the most important of which is the "giant tamilok", the largest shipworm species in the world. The species can only be found within the area, and no where else in the world, making Kalamansig an important biodiversity area. Formerly hunted by the locals, the giant tamiloks are now strictly protected by the municipality, specifically the former hunters of the species, after research confirmed the high importance of the species in the area's biodiversity.