Does an employer have to inform you if you are being recorded?

I am not asking about the legality of if they can record you but I am wondering if they have to inform you that you are being recorded and possible having some form (in an employment contract or otherwise) signed acknowledged that you have been informed you are being monitored?

I haven’t done anything wrong but I recently discovered there are cameras all over my building that are actually on and recording and my employer told no one.