I have a friend that talked to an older gentleman that raises chickens. The supposed comment was to add another rooster. Take it for what's it's worth. (shrug)
My area just went through a spell of hot humid weather(no breeze) 3 box fans running with cardboard lining the walls of the coop.
Chickens started panting. One by one I soaked them in a rubber tub full of water to cool them off. They didn't fuss, and just stood in the tub until they cooled off.
This sounds very familiar, however, I try to discourage the chickens to Not go in the woods since the local wildlife I have matches yours.
I box trap any unwanted critters, luring them in to the trap with part of a banana. Raccoons seem to love bananas.
No ravens here... but plenty of "birds...
The waterer most likely has a galvanized (toxic) coating to make it last longer. If it's rusty on the inside, it is probably not safe for your chickens to drink from.