Yes, rats are a very real danger to chicks and I have heard that they will eat the feet off confined chickens and rabbits so you have to take all into consideration. I lost my first pullet to a rat in May this year. At first I thought my dogs had gotten her but on close inspection, her hear had been eaten out of her as if a surgeon had taken it and not a spot of drool on her so then I came to my senses and realized no way it could be the dogs.
Next the rats got one whole new chick in June and just a head off another who they tried desperately to pull through a section of chicken wire but the chick of course wouldn't fit so they settled for eating her head. ( had an outdoor baby pen)
Finally I was sitting home with the window open and my chicks outside at 1:30 in the afternoon, broad daylight and hear my chicks going off! I ran outside so fast that I was barefoot still. To my horror, I see a big brown rat on top of one of my chicks back, inside the pen and biting away! I will NEVER forget that image! My Doberman had come out behind me and I kept telling him GET THE RAT! GET THE RAT! He didn't see the rat for a few seconds, then he saw what I was freaking over and by this time the rat, who had it's back to me, engrossewd in eating the chick, realized it was screwed so it kept running around in the pen trying to get out. The rat disappered under my truck when it found it's way out and my dog went after it but came back in a minute so I was really bummec that it got away.
Meanwhile I picked up the chick and held it and although the bite on it's back did not apppear to be deadly, she just shut her little eyes and gave up living. Someone told me she likely died of shock. I was so PO'd! And finally sick to death of rats. Someone on a dog list told me to pop my poison blocks down their holes. (These are Norway rats here who like digging mazes of burrows in the ground.) I had been afraid to do that since the poison maker advized not to on the packaging.
I went around my truck to put the little body in my trash and there laying in a patch of crushed flowers lay my killer rat, all dead! My wonder dog had caught and killed her but he forgot to tell me when he came back a minute later! That dog got extra treats that day!
Right after that I said screw it and dropped blocks down every rat hole I could find and wound up with like 13 dead bodies, just in my yard. No telling how many I killed in all. I figure if there are so many that they would kill in broad daylight then I better get a grip on the situation and so I did a no-no. There must have been so many that they ate every bit of poison and even if some remains, it is still buried under ground in their fairly small burrows.
I'm sorry you lost your rare chick. I say use the blocks. The stuff I used was called Real Kill (I think--it was green blocks, about 1/2 inch square-I could only find this at Home Depot) I have used other stuff since with the new rats that have taken over the barn, but they just eat that like candy and I have gotten no bodies! The new stuff was yellow and they just consumed that like crazy.
