If your Cockatiel is a little too excited when it’s feeding time then he may be prone to food aggression. Does he try to attack your hand as you reach in and fill his food or water bowl? This could definitely be a sign of food aggression, which should to be talked over with your vet. Your vet should be able to help you determine if the aggression is pertaining to just food or if there are other times when your bird is showing aggressive behavior. Signs of aggression include elevated feathers on the nape and neck, open beak, fanned tail feathers, and even eyes that appear to be very wide and excited. Typically, aggression is the result of fear or perceived danger. If it’s mainly food aggression then your bird may be afraid he will not be fed. Your veterinary clinic Walnut, CA may suggest feeding your Cockatiel at the same time daily to help lessen the fear. Visit website http://diamondbarvet.com/