I live in the "burbs" of Portland Oregon and other flock friends have seen hawks dive right into their small yards and kill a chicken--while they are standing in the yard!!! Talk about shock and awe!!
Perhaps they are bolder in the city?? All I know is it is a real threat right in and around the city. We have plenty of raccoons and coyotes too. My yard would be a 5 star restaurant for the raccoons as we have 2 ponds with fish as well. One is 1,100 gallons and the other is much smaller at 150 gallons. My defenses?
1. Forte Knox coop and run. Netting over extra run.
2. Never leave the house without putting the girls back into Forte Knox (our coop is affectionately called "The Egg Plant)."
3. Our ponds have no shelves for plants near the edges which leaves no place for raccoons to wait and grab at the fish. The sides drop to nearly 3 feet deep right next to the
edges and they won't won't jump in and swim after the fish. Both are above ground ponds too.
4. We have netting over 75% of the pond so Herons will not touch it (they fear getting tangled).
5. A trained Belgian Malinois who takes guarding her yard seriously--chickens and fish included.
6. I also love our murder of crows who although on occasion are annoyingly noisy they do keep the hawks from staying long in the towering evergreen trees next to our yard.
My recommendations to consider:
Scatter the netting in workable blocks so you only have to put supports for it in a few parts of your yard.
String up fishing line with hanging shiny objects on it to connect the nets.
Add cover for the girls in various places as others have recommended.
Shiny objects may also attract crows!
This should make it seem like a real obstacle course and you won't have to net the entire area end to end.