Menhaden are omnivorous filter feeders, feeding by straining plankton and algae from water. Along with oysters, which filter water on the seabed, menhaden play a key role in the food chain in estuaries and bays. Atlantic menhaden are an important link between plankton and upper level predators. Because of their filter feeding abilities, "menhaden consume and redistribute a significant amount of energy within and between Chesapeake Bay and other estuaries, and the coastal ocean." Because they play this role, and their abundance, menhaden are an invaluable prey species for many predatory fish, such as striped bass, bluefish, mackerel, flounder, tuna, drums, and sharks. They are also a very important food source for many birds, including egrets, ospreys, seagulls, northern gannets, pelicans, and herons.