Sorry for the loss Duane but that hawk was doing what it was born to do-hunt prey. I hope you can get replacement birds. Still a shock to see that big bird where chickens should have been! We can have chickens here but not roosters. I would but there are too many outside cats roaming about so it really wouldn't be fair to the birds. I have a hard enough time keeping my wild birds safe from the cats let alone the red tails. My feeder area is covered by reed fencing so it gives the birds a sense of protection. When they're out foraging in the leaves I think that's when they are most vulnerable.
