The following spring they migrate northward as adults to the Chesapeake Bay area and into New England waters. Atlantic menhaden are one of the most abundant fish species in estuarine and coastal Atlantic waters. During summer months in Chesapeake Bay, these fish swim in large schools and their silvery bodies can often be seen splashing the water's surface. Juveniles primarily feed on zooplankton, but adults are mainly herbivores, but retain the ability to feed on zooplankton. The adults are very adaptable and will feed on several species of phytoplankton, as well as suspended organic plant detritus.
Atlantic menhaden are an ecologically critical fish species.
They consume and redistribute a significant amount of energy within and between Chesapeake Bay and other estuaries, and the coastal ocean. This is due, in part, to their tremendous numbers, their individual growth rates, filter feeding capacity, and seasonal movements. Menhaden are also an extremely important prey species for many predatory fish such as striped bass, bluefish, Spanish mackerel, tuna, and sharks. Because of their schooling behavior, they are also a favorite target for herons, egrets, ospreys, and eagles. Management authority was established in the states because the vast majority of menhaden landings come from state waters.