Animals in the intertidal zone make up a complex community. Many animals live together in small spaces. Under one rock, you might find several different snails, worms, crabs, sponges, and anemones living side-by-side.
However, sometimes animals must compete for the best living spaces. Some need protection from the water, sunlight, and predators who eat them. Biologist Patrick Green got a "first-hand" (pun intended) experience of this not-so-neighborly competition when he went looking for a resident. Mantis shrimp live in holes in the rocks. Instead of finding a shrimp in one burrough, he found an octopus! This video shows what happened when he startled it!
by Nina Dropcho