I live in upstate NY, weather is just starting to break here. We have a lot of fox, coyote, weasels, and even bobcats had been spotted here.
Welcome fellow upstate NY''er.
Sorry about your BR.
So hard to tell what critter did the deed. I've been seen a few of fox, coyote lately, but I've seen more skunks than anything. Get a trail camera and set it up near the coop/run. Whatever took the chicken will probably be back and you'll have it on camera.