Tidepool Tim says,  “Dogwinkles are an interesting snail because they live in the middle of the intertidal zone.  These are predators that feed on other mollusks like blue mussels, periwinkles or crustaceans like barnacles.  They use their toothed tongue or radula to bore a hole into the shell to access the soft parts of their prey. When we need to collect dogwinkles we search the rocks under the largest beds of rockweed.  Groups of dogwinkles are scattered among these beds - it is kind of hit-or-miss. Dogwinkles are great aquarium specimens and seem to live for extended periods of time on the glass sides of our tanks. Seagulls seem to be the biggest predator on this type of snail. We have found dead dogwinkles that are cemented to rocks by the byssal threads of blue mussels.  It is thought that mussels lash them down with their threads as a way to prevent predation. The winkle, once latched into place, cannot move to feed or get to water eventually will die.”