I'm trying to think if who's knowledgeable about snakes that I can tag.I wonder if a snake with a half inch span manage to a bird down that far, I know they can unhook their jaws but that's a large bird. Morbid curiosity would have me taking some pliers to those feather shafts to see if...
I'm sorry you lost a bird. How far apart are the marks? Can you tell if they're punctures? They certainly look like fang marks to me but I've never had a problem with snakes in my coop.