The number of bowel movements that a bird has per day depends on his size. While budgies go dozens of times per day, a larger bird like a macaw may go as few as 15 times. Birds can be trained to control their bowel movements and hold their waste; but unlike domesticated animals that can be potty-trained such as dogs, birds have to go so frequently that rigid potty-training can result in them hurting themselves by holding their waste. Because a pet bird may have to go as often as every few minutes, you should learn to recognize the signs that he is about to have a bowel movement and accommodate him rather than train him to suppress them. If he resists sitting on your shoulder, for example, it may be because he senses a bowel movement coming.