Amphipods eat decaying plants, algae, seaweed and fish. There are deep sea amphipods and amphipods that live on the shore, eating seaweed and burrowing into the sand. Amphipods may also live in tide pools, near coral reefs or rocks, and are easy to see on the sand.
Scientists noticed that one type of deep sea amphipod, H. gigas, was particularly large, which was surprising considering the lack of decaying food available near the bottom of the ocean. They discovered that these amphipods had an enzyme that allowed for the digestion of wood, and this species was gorging on branches and sunken ships that were decaying.