I love my roos, and have even managed not to kill the evil one that was incorrigable attacking ME. Not the dogs, not anything that truly was a threat. I put him in his own place with his own hen...the RIR roosters are great, no attacks on humans!
How do you mean "protect" I really haven't seen them protect except to attac humans (me) as I am sure they think I am a big rooster after their hens. They let my German Shepherds do anything they want! Unless you mean that predators tend to go for them first as they are loud and attract attention when a predator comes in (back in the early days of my chickening, if a dog came in it got the roosters first, sometimes not the hens at all, but I did not see how this happened...),I wonder if in the same way they echo a hen cackling that she has laid an egg to distract? Seems like an egg (or hen) seeker will be confused.
Roos would have more friends if only they didn't crow at 3 am sometimes, actually, often. My new to the country son in law has an unfortunate dislike of chickens due to some long nights when he moved to a farm with game roos crowing from the trees near his window, I'm sorry to say. No chickens for them! Now he has a baby that crows at 3am!
The crowing doesn't bother me a bit or wake me...but if something is riling up the chickens, I wake right up! Hens can be quite loud too, but more during the day than the night.