The Order Pelecaniformes consists of medium to large water birds, including pelicans, herons, ibises, and cormorants. Members of this order are adapted for aquatic habitats, often feeding on fish or other small aquatic animals. They typically have webbed feet for swimming, long bills—sometimes with specialized structures like the pelican's pouch—and strong wings for sustained flight. Many species nest in colonies near water, and their social behavior ranges from cooperative fishing to communal roosting. Pelecaniformes play important ecological roles in controlling fish populations and maintaining the health of wetland and coastal ecosystems.