Has anyone compiled a fairly exhaustive list, of all the foods which wrens will eat in very severe weather, i.e. when the ground and vegetation in covered in snow for long periods?

They eat small animal life around pond edges, hence I leave lots of bowls, tubs and other containers in my garden, generating lots of water lice. However, they are of no use when frozen over.

Some books state that in severe weather, small seeds and fine crumbs of cheese, cake and biscuits will be eaten.

It is also stated that many die in severe weather but numbers quickly bounce back, in good breading seasons. We could just let them die of starvation in severe weather but I'd like to provide appropriate foods, if possible ...