How big are your pullets? If they are still small I would worry about the rooster being too rough with them. Also the two roos may not get along, but I'd say the sooner the better. Separate the two groups if you can....put the rooster in a pen inside the coop, so they can meet but not make contact until they seem aquainted....in a week or so.

Never had this situation myself, but I would not personally put a mature roo in with such young pullets with no mature hens in the pen. It is different when a broody raises chicks and the roo has known them from the beginning and has plenty of mature hens to jump... but I would worry in this case that he may be very hard on them sexually. Will your friend keep the roo for another six to eight weeks? If so, that is what I suggest.

Victoria's suggestion of letting them get acquainted through wire for a few days is a good one, I think. I am assuming that "The King" will be the only roo amongst the fifteen pullets. That is a good ratio...he will tend to spread his favours around, which is easier on the hens.

Thanks for the suggestions. Yes, "The King" will be the one and only rooster. I'm sure my friend will hold him until I can safely incorporate him into my flock.

--Johanna