Do waxwings eat anything in winter besides berries, such as snow or tree sap?

Yes. Berries and other fruit dominate the winter diet, but it is broader than the familiar picture of a waxwing holding a rowan berry.

Snow and water: while feeding on concentrated, dried fruit in winter, waxwings may drink often and eat snow.
Tree sap: in late winter and spring they can take sap from maple and birch trees.
Insects: they catch insects in short flights from exposed perches. Insects are an important part of the summer diet.

Waxwings swallow fruit whole.

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