Pineapple has a high sugar content, but swans can't eat food with high sugar content, because eating it will cause indigestion in their stomachs and even endanger their health.
Swan generally likes to eat aquatic plants, such as lotus root, Elaeagnus Elaeagnus, aquatic plants and so on. Swan sometimes eats grains and seedlings in winter. Besides plant food, swans also eat mollusks and aquatic insects. Swan mainly forages in the morning and evening.