Re: small hive beetle in michigan?
If I were guessing I'd say that your beetles arrived with your new bees or came off of some migratory hives nearby. I don't think you are likely to have an ongoing problem in Michigan with shb.
In my hives most of the adult beetles die during our winter. They don't usually recover enough to become a serious problem until late July. Your winters are longer and colder. The few that might survive have a much shorter season to build up. If you keep your hives healthy, I can't imagine that you need to do anything else.
I would be a bit concerned about the larvae on the topbars. I believe that I would remove the propolis trap.
PS I don't use traps or any other management for shb with the exception of keeping my hives in full sun and keeping them healthy.
Don't worry too much.
Let me never fall into the vulgar mistake of dreaming that I am persecuted whenever I am contradicted. - Emerson