Juvenile walleye pollocks, Theragra chalcogramma, in search for prey such as small fish and zooplankton. The squat lobsters, Munida quadrispina, eat zooplankton as well, and use their antennae to detect zooplankton movement in the water. Pacific pollock are known to swim in groups or in isolation. The squat lobsters, M. quadrispina, all have their backsides facing some variation of a barrier so that possible predators cannot sneak up behind them. Notice the extended chelipeds ready to defend.
The Plumose anemone, Metridium senile, has retracted its tentacles inside its gastrovascular cavity because it is either digesting food, or felt threatened and is protecting its soft oral disc.
The Pyura tunicates, located above the largest squat lobster, are in the Phylum Chordata. All vertebrates, including fish and humans, are in this phylum as well. Tunicates are sessile, have an excurrent and incurrent siphon for filter feeding, and may be solitary or colonial.
Syringella sponges are located in the upper left corner, and are covered with sediment. These sponges are sessile and small crustaceans, like squat lobsters, may use them for protection. Like tunicates, sponges are filter feeders, but have porocytes instead of an incurrent siphon and have an osculum that’s similar to an excurrent siphon.