Hermit Thrush--in December?

Back at the end of October, in the post Hermit Thrush, I reported a sighting of a slightly late migrant hermit thrush in the cedar bush, pictured at the right. Yesterday, in the dusk-like conditions of a snowy day in the middle of December, there it was again, in the cedar bush.

I like a thrush--as I think I've said before--so thrush-like. I was puzzled by this bird yesterday, first thinking it was a robin (they sometimes spend the winter back there), then, given the size, some strange sparrow. But after a moment or two of looking and listening, I realized that it was a hermit thrush. Soft call, dark spots at the top of the breast, and this bird was flicking its tail and dropping its wings in much the same way as my October bird.

It really is winter.
Wondering what it could mean, I checked my thrush sources (Sibley, first of all) and learned that this thrush, unlike most of the others who hang around here in better weather, is not a long-distance migrator. Most Ontario thrushes spend the winter far, far away. Here is the WildSpaces range map showing the wintering area for the hermit thrush; compare that to the winter range of the veery, another woodland thrush that breeds here.

The life history of the hermit thrush describes it as primarily insectivorous, with no second option. This is interesting for a bird that normally winters as far north as the information provided suggests. Its food-gathering techniques are described as gleaning and foraging--even foraging isn't going to provide much in the way of insects in winter in the northern portions of its normal range. This article at Birds by Bent however describes the winter diet of the hermit thrush as being largely fruit. Fruit was good this year around here, so maybe this bird will make it through even if it doesn't move on.

Added later: The "life history" linked above that suggests that the hermit thrush is exclusively insectivorous is at Wildspaces, and concentrates on the diet of the bird when it is in Ontario--i.e., during the spring and summer--probably why they don't mention the fruit it eats in winter. On the other hand, reports from Christmas Bird Counts, which start in the middle of December, are now pouring in from around Ontario, and the hermit thrush is showing up in quite a few of them. Not in huge numbers, but certainly often enough to suggest that, like the robin, this thrush is a winter bird in southern Ontario.