[geohamster]

Thank you Amethyst and Ria for your thoughtful, helpful, and well considered answers. The substrate is standard Pets at Home wood shavings, unscented. It is very interesting about the low energy torpor state. Although we have had some very warm weather, the episodes have not been at particularly warm moments. It happened again with Dusty yesterday, but she revived very quickly. He is only eight weeks old, so perhaps it might be something he grows out of. As I said, it also happened once to Poppy; but over the last six months, there has been no recurrence. I haven’t spoken to a vet because I really can’t believe that there is anything of it could do; if a human were behaving in such a way, I suspect one might put him or her on some very potent medication. Not something that would be available or recommended for a hamster.