I believe the free range ones that survive most are the coward for lack of a better word. The strong, confident courageous ones will stand thier ground and most likely be killed by whatever predator it may be. Fox, dog hawk etc. On the other hand the cowardly ones will run and hide to live another day. Just my opinion but I do believe itI free-range 24-7 in an environment that is likely more predator dense than most keepers here. I strongly reject the proposition that successful free ranging depends on having low predator numbers. “I can’t free range because I have too many predators” is almost always the factually incorrect answer. A more proper answer is “I can’t free range because I raise chicken breeds not suitable for it, and I do not do my part to persecute predators so that when they enter my farm, they’re skittish and afraid to linger long.”
Natural selection used to be the dominant force in determining which chickens survived to create the next generation. Human selection was secondary. In the last 100 years, human selection has become entirely the driving force behind shaping chickens. In that sense, I decry the modern trend towards coop keeping.
Although I don’t actually care how a person raises their chickens. I more lament the loss of knowledge that chickens more normally lived free range throughout their domesticated history. I fault no one for keeping their chickens in a Fort Knox coop. What is a pet peeve of mine is when coop keepers declare their way is the only way to raise chickens and that chickens are incapable of living otherwise.
I often use domestic dogs to analogize the actual abilities of domestic chickens. We all understand that some dog breeds are meant to be soft house pets and others are built for harsh working conditions more akin to how wild wolves live. Chickens are the same. Its just that the wolf-like chickens have been forgotten over the last 50 or so years and that most common chicken breeds today are all the equivalent of lap dogs.
Along those lines, there is a common misconception that domestic chickens have been slowly evolved towards weakness over thousands of years. In reality, the morphing of rugged free-range breeds into soft coop breeds has happened twice, and both times it only took a couple of centuries of selective breeding. The Greeks and Romans made the first coop breeds from gamefowl (fighting chickens). When Rome fell, there was no more global economy to cheaply feed coop birds. The coop doors flung open and only gamefowl and those coop birds that could revert to a wild state survived. Through the Middle Ages, chickens lived free range around human settlements. Only since the modern era have we been remorphing them back into coop breeds, and our modern coop breeds haven’t passed the test of time.