Nutrition
Clupea pallasii (Pacific herring) eat many different things, depending on the stage. They feed by taking the food in through their mouths. The herring larvae feed on mainly ostracods, copepods, other fish larvae, euphausiids, and diatoms. Young herrings feed on mostly crustaceans, zooplankton, other small fish, worms, clams, and eelgrass beds. Adult herring also feed on crustaceans, zooplankton, and other fish, but they can consume much larger organisms than the young herring. The adult herring also feed on copepods, amphipods, and euphausiids. The adults migrate daily up the water column to feed on these different organisms. To intake this food, the herring swim with their mouths open so that that the plankton can be caught.
Diatoms