I think I either have an exrtremely colorful female on my box or the male has been in there. I only catch he or she flying out as I approach. Do the dads ever stay on the eggs. It has been unseasonably cool lately.
They do not have a brood patch so it is highly unlikely although he may have been doing some housecleaning like all good husbands should! I have had a male pop in and out when the female is out hunting but usually no more than 2 or 3 minutes.