So sorry to read about your two girls. It hurts and the guilt just eats us (some of us) alive after somethinglike this happens. I walked out to see a big ol'behemoth Bald Eagle sitting in the tree this morning. Took some talking but I finally got it to take a hike. My chickens, 3 adult geese, and 21 ducks are all in the same yard and all go in at night together. Sometimes the water fowl take their time especially when it's cold out. But everyone gets along just fine. The ducks and geese most definitely have a keener eye for sky dangers. They can spot a hawk that I can hardly see and the chickens haven't noticed at all. In that respect, yes they are kind of protectors.