The emperor shrimp develops a symbiotic relationship with a range of nudibranchs and holothurians, or sea cucumbers. The shrimp lives on the surface of the host, which offers him protection from predators and an extra source of food. The relationship benefits the host, as the shrimp consumes any parasites on its skin. The shrimp doesn't stay still, but constantly moves up and down his host, looking for food from the substrate or that has been disturbed by the host.