During the Maastrichtian stage the Western Interior Seaway, which stretched in a north-south direction from the present-day Arctic Ocean down to the Gulf of Mexico, separated "Dryptosaurus" and its coeval fauna from western North America which was dominated by tyrannosaurids. Although certainly a carnivore, the paucity of known Cretaceous East Coast dinosaurs make ascertaining the specific diet of "Dryptosaurus" difficult. Hadrosaurids are known from the same time and place as "Dryptosaurus", the island continent of Appalachia, and they may have been a prominent part of its diet. Nodosaurs were also present, although less likely to be hunted due to their armor plating. When hunting, both the skull and hands were important for the capture and processing of prey.