Caddisflies: Trichoptera - Diet

Adult caddisflies eat only plant fluids such as nectar or sap. Depending on the species, the larvae eat bits of plant materials on the bottom or in the water, living plants, living and dead animals, or most or all of the above. Species that do not build cases usually feed on tiny bits of plants or prey on other insects. Case builders shred leaves, graze on living plants, or scrape algae (AL-jee) from rocks, wood, and other surfaces. Some species use their jaws to pierce threadlike algae and suck its fluids, one cell at a time.