Aquatic plants: They mainly feed on aquatic plants such as pondweed, water lily, and algae, which they obtain from the water bodies they inhabit.
Submerged vegetation: They dive underwater to reach and eat submerged vegetation, including roots and stems of aquatic plants.
Grasses: Mute swans also consume grasses along the shoreline and in shallow water areas.
Plant matter: They feed on plant matter, including leaves and stems of various plants found near their water habitats.
Insects: Mute swans may occasionally consume aquatic insects, small fish, and invertebrates when available.
It's important to note that their exact diet can vary depending on the specific location, habitat conditions, and available food sources.