What Food Do American Flamingos Eat? American flamingos have a unique and specialized diet that plays a big role in their vibrant pink coloration. These birds primarily feed on small aquatic organisms found in shallow waters such as algae, diatoms, tiny crustaceans (like brine shrimp), mollusks, and aquatic insects. The most critical component of their diet is carotenoid-rich food—especially algae and shrimp—which provides the pigments that give flamingos their signature pink hue.