i was looking at my hive today and i saw bees that were much bigger than my bees and much more black (i have italian bees). does anybody know what these bees may be and should i be concerned?
Probably drones from local area.As it gets closer to swarm season you will see them around your hives more.
If your bees were form a package, the queen may have come from a different stock and now you are seeing her offspring.