Some chinchillas will learn to adjust their sleep schedule according to your schedule and some will just do whatever they want. I have two 1 year olds. The female is often awake during the day and always begs for my attention. She will take naps in between but mostly sleeps between 4-8 am. On the other hand, her cage mate insists that he needs his sleep during the day and will not wake up until 6 pm (even if she steps on him or if I poke him). After that, he is active until 4 am. They are both most active at 2 am and will eat the most at that time.
You should also be aware that some chinchillas will sleep because they are bored. So you can try to bond with him or engage him in some toys or activities every time you see him awake, just to let him know that he's not totally alone. Chinchillas are very social animals, if you can't spend enough quality time with him, you should consider getting him a cage mate. You will notice a change in behavior instantly.
-ChinchillaBoston
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