Black drum are a common and widespread fish species found throughout coastal waters, ranging from New England down to South America. These fish are known for their distinctive habit of foraging along the seafloor. As bottom dwellers, black drum primarily search for their food in the sediments of estuaries, bays, and nearshore ocean environments. Their feeding strategies are particularly adapted to their preferred prey.
Primary Food Sources
Black drum predominantly consume invertebrates found on or in the seafloor. Mollusks, such as clams, oysters, and mussels, form a significant portion of their diet, with black drum showing a particular preference for these hard-shelled bivalves.
They also feed on crustaceans, including different types of crabs like fiddler crabs and blue crabs, as well as shrimp. Marine worms are another food source for black drum, which they often root out from the substrate.
While their diet primarily consists of these benthic invertebrates, black drum will also consume small, slow-moving fish. Research indicates that black drum near oyster reefs may prefer oysters, consuming an average of one oyster per pound of body weight per day.
Feeding Mechanisms and Behavior
Black drum are specialized bottom feeders, using unique adaptations to find and consume prey. They swim with heads lowered, using whisker-like barbels to detect food buried by feel and smell. This often involves rooting into the seafloor, creating “drum noodles” as they search for mollusks and worms.
Once food is located, black drum use powerful, pavement-like pharyngeal teeth in their throat to crush hard-shelled prey. These specialized teeth are developed and allow them to effectively break open the shells of oysters, clams, and crabs. After crushing, they eject shell fragments from their mouths.
Black drum can also produce a drumming sound by vibrating muscles against their swim bladder, though this behavior is not associated with feeding.
Diet Across Life Stages
The diet of black drum changes as they grow, reflecting their developing physical capabilities and habitat shifts. Larvae primarily feed on microscopic organisms like zooplankton.
As juveniles (typically under 8 inches), their diet shifts to smaller, softer prey such as marine worms, small shrimp, and tiny crustaceans. Their mouths and crushing plates are not yet fully developed for larger, harder-shelled items.
Once black drum grow larger (usually beyond 8 inches), they begin to incorporate more substantial and harder-shelled prey into their diet. Sub-adults and adults increasingly consume mollusks and larger crustaceans as their pharyngeal teeth and jaws become strong enough to crush these tough shells. This dietary progression often coincides with their movement from shallow, estuarine nursery areas to deeper coastal waters and oyster beds, where hard-shelled prey are more abundant.