This is definitely NEWS OF THE WEIRD. Why GLUE cowboy hats onto pigeons? In Las Vegas? Does Las Vegas even count as The West? Technically? I hope no pigeons were harmed in this whatev and that the pigeon-rescue group can remove the hats. Though I gotta say, the pigeons are stylin'.....
You could do it with LOW-temp glue gun, would come off with a 10-second blast from a hairdryer & a gentle tug. I sometimes put a feather in my hair that way.