What sea creatures live in flocks?

Many sea creatures exhibit flocking behavior, most notably various species of fish, such as sardines and herring, which form large schools for protection against predators. Some seabirds, like puffins and pelicans, also gather in flocks while foraging or migrating. Additionally, certain marine mammals, such as dolphins and orcas, are known to travel and hunt in pods, showcasing social behavior similar to flocking. This group behavior enhances survival and increases foraging efficiency.