Nucella lamellosa (Gmelin, 1791) is a phenotypically plastic species that preys on barnacles and occurs intertidally and subtidally along the north-eastern Pacific coast. This laboratory experiment tests the hypothesis that daily episodes of emersion impose a greater stress than daily episodes of limiting food in N. lamellosa. In this experiment, individuals of N. lamellosa were housed in containers with a rock covered with barnacles. In one experimental treatment, I removed snails from their barnacle-covered rocks and placed them on a counter for five hours each day. In another treatment, I placed the snail-and-rock assemblage on a counter for five hours each day. In a final experimental treatment, I kept the snails submersed, but placed the barnacle-covered rocks in an empty sea table for five hours each day. A control treatment kept individuals constantly submersed with continuous access to food. To account for the effect of handling the snails, individuals in a manipulation control were picked up and then immediately returned to their rocks. When individuals of N. lamellosa were removed from the water without their barnacle-covered rocks, they ate significantly less than snails in either control group and significantly less than the snails that were constantly submersed but without food for five hours a day. This result suggests that daily episodes of emersion are more stressful than daily episodes of limiting food.