My turkeys have some food aggression. Whenever I enter the yard, they crowd me and grab stuff out of my hands. When my chickens get pushy, I tap them on the head and they back off. This doesn't work for turkeys. What is the turkey equivalent of pecking/tapping on the back of the head to stop unwanted behavior? I need something like the Dog Whisperer, who can say "Tssh" to a pack of dogs and they all back off.