By the way, the "It's not yours, leave it" would be okay if it was on the owner's property, and of course that would be the correct response. But the broody is on the NEIGHBORS' property. You're putting the burden of conscience for the broody's safety and the consequences of her nesting site, on the neighbors' shoulders. The person whose property it's on has a right to a say, here. I sure as hell would feel awful if someone's hen nested in my fountain and i just let a hawk come snatch her on my watch. If the owner doesn't care where she is, that puts the burden on me. Think of the hen as a living entity, not property, and act to protect HER (and her brood). THEN it's a "no brainer."