Thank you for all the welcome posts!
DOG UPDATE--I took Porter (our Great Dane) out on a leash yesterday after I posted this and worked with him in the chicken yard. He walked right in and started excitedly sniffing around, the first chicken he went up to and started to sniff, I loudly commanded NO and slapped his nose. He immediately stopped and sat and looked at me for assurance. I praised him and we continued to follow the chickens in the pen all the while verbally praising him and saying how good he was and patting him on the side and petting his head, he never once tried to sniff or lunge at them. I open the pen door and let the chickens out and we still followed. Even when the girls came over to him and pecked his foot he still did not even look at them. After a while I dropped the leash and walked around. He sat still and watched. After I removed his leash, he made a bee line for the back door and laid down. He has been out with them ever since and has not even looked their way!! I should have done that a long time ago. I never thought it would be that easy! I still would never go off and leave them alone, but now when we are home their door can be left propped open.
Still pecking though. So now they have been out on an acre of land most of the day yesterday and half the day today. I just witnessed the one red still pecking at the others while in the field. So I think I can rule out boredom, and lack of space/ overcrowding. It is not hot and they have been eating mealworms I give them and catching grasshoppers.
.