Food for Yellow Wagtail

We live in Windsor Berks and have a small ornamental pond in the garden.

We are very excited to be visited by a beautiful bright yellow wagtail.

I understand that it is not normal for the yellow wagtail to be around after September and that the bird is on the Red list.

We are keen to help feed the bird but understand that it feeds on small insects and beetles.

We put out general bird foods including seeds, dried mealwaorms, peanuts, and fat balls etc.

Can anyone tell us if there is a food that we can buy that will help the wagtail through the winter.

Thanks.