Some invertebrates are carnivorous. For example, jellyfishes and squids often feed on fishes, while octopuses prefer crab dinners on the sea floor. Dog whelks and some sea stars prey on shellfishes, such as barnacles and mussels. Sea snails, chitons and sea urchins are examples of herbivores that graze on algae, seaweeds and other plants. Others scavenge, and some are omnivorous, feeding on whatever food is available.
Many carnivorous invertebrates rely on camouflage to lure their prey.
Others scavenge leftovers from meals of other animals. Some invertebrates are parasites that live in or on other animals and derive nourishment from their host species. Some invertebrates live symbiotically with other organisms. Another example is the association between sea anemones and clownfishes. The clownfishes gain protection while the sea anemones get bits of dropped food.