It is a widely distributed waterfowl of the duck family. Known for its bright green head in males and simple brown feathers in females. Medium in size, males are usually more prominent than females, with a distinct green crown and white neck ring, while females have a brown body with mottled patterns. It is an omnivorous animal that mainly feeds on aquatic plants, insects, small fish, and small aquatic animals. It breeds in many wetlands, lakes, and rivers in the northern hemisphere, especially in Europe and Asia. It is a migratory bird that flies from its breeding grounds to its wintering grounds every autumn. The migration route covers a vast area, sometimes even crossing continents.