I do this with my chickens; it can be very useful to have them come when called! I start when they're small, giving some kind of treat while calling "Chick, chick, chick" and before long they learn that means something good. I also use specific containers for specific treats, such as a coffee can for sunflower chips, and a Glad disposable container for the mealworms... they get VERY excited when they see that one!!