I have never seen a chicken that was not instinctively wary of things overhead. No training necessary, regardless of how they were raised.
Since night time predators are more likely to be effective in killing I trained mine to go back to coop and lock them up at night.
During the daytime they free range without restrictions except for my body and my walking staff (used like a herding stick) to 'train' them away from the road so they won't get hit by car or stray too far get into the sharecroppers plot across the street. (Don't want mine getting used to eating in soybean or corn fields).
My term training was referring to me acting as a herder I guess you'd say to teach the unacceptable to cross barrier set for them. I yell 'back, back' and move quick (as I can) to get between them and the "no no" areas if need be stretching out my walking staff to nudge them away or herd them back.
Then all I have to do is watch from the door if I go in to eat and yell "back back Baaack". They turn back every time so far.
I have noticed chickens inside fenced areas or with overhead wire aren't as fast to act on their natural instincts for protection. Then if they ARE out true free ranging (no restrictions) they are more lax and more will get caught.
As you can tell I am an old fashioned husbandry care person. But then my environment lends to this type of management. If I could afford to and physically, medically handle a larger farm endeavor I would. But I am NOT they type to use chemicals to improve the production of such. I have used no chemicals at all on this property since I moved back here. Now the interim between my high school years/my family owned and my return it was "the cabin" for my married life period. The husband then did to my objections use round up or other strong killers on burdock etc.
Funny but I have less of those pesky intruders than we did back then. We had more and more when he was sneaking around with the squirt bottle. LOL my methods work better... though it takes time, attention and persistence.
Just like proper breeding and poultry management.... you have to spend time with them, observe them, and learn what their requirements are to live at their best naturally. Not many have the patience now days to do this type of management. This I want it, I want it now attitude and way of life is why there are so many neurological problems etc with our children and changes for the worst in our environment today. (I CAN say this as I experienced first hand the permanent physical health effects from exposures. The worst in my book was a husband who KNEW chemicals caused a respiratory problem for me and would pour or spray them on the pillow beside me before I woke.)
I live alone now with my chickens, cats, fish tanks and my wildlife on the property now. Past has had lasting effects on my body but I pay attention and manage to keep any further deterioration at the minimum. I find ways to get around the "normal" way of doing things to get something done. I drag instead of lift. I get laughed at by friends for crawling or dragging my body to do work in garden when I have to as I can't squat very well. But hey I DO IT. Might take me longer than a strong bodied person but I refuse to give up. This is ONE of the reasons I have my chickens to begin with. I may not be able to hold an income generating job but I eat and feel a purpose in life from activities of my own hands. I see NO purpose in sitting somewhere watching TV, waiting for someone to bring me what I need to stay alive, or even BEING in a place where I can not plant food and have to beg Government for money so I can pay someone to buy food from the store which is laden with stuff I shouldn't be eating anyway.
I think I may be living in the wrong time and Era ..... oh to be where the picture is: you supplied me with some grain or alfalfa, or your cow manure/bedding and when I cull I supply you with the meat or some eggs or some other things swapped out of the garden. Knowing that if I ask for help others will know it is because I truthfully need a little to get me over a hump. Am I nuts to prefer to get help with heating costs than to get too much in food help and nothing else?
Ok ENOUGH of that, off my soap box now. Wishing to all a productive day in whatever way you call productive!