I'd be willing to bet they are getting ready to go down. Most adults in the wild are nearing this, and it's probably much warmer in their native habitat that in Davis. If they have reasonable weight you might just hold off trying too hard to make them eat and see what they do. If you plan to hibernate outside be sure their cages won't flood this winter. But there should be some moisture in the sand so they don't dehydrate.
Do you have any pics?
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