The first two things to look at are dedication and speaking ability.
Are you dedicated to training your parrot? This can be a very slow process and will require a lot of patience. They do not know what you want them to do, so it is up to you to teach them that. The more human interaction you have in training your parrot, the better your results will be.
What is the birds general speaking ability? Do not expect a cockatiel to speak like Alex the African grey. Not all birds will speak either. Just because you own an African grey, doesn't make him a good talker. He may not be a talker at all, or he may never shut up. Choose your bird wisely and spend a lot of time with them and chances are you will be rewarded. Birds should be chosen for companionship anyway. Talking ability is just a plus.
So what is the trick? Positive rewards. Plain and simple. Rewarding a parrot for a positive behavior, no matter how minute, is the best way to train a parrot to do just about anything you want. Just as you teach a child to talk, it is the same for parrots. Repetition is the key. Repeating the word over and over and rewarding for any attempts. Find your parrots favorite cracker, seed, treat, etc and give it to them right after they make an attempt at what you are wanting. Eventually they will repeat exactly what you want and guess what, since you were positively rewarding them, you can now get them to do it on command.
Usually parrots learn their names first. Why is this? Because they associate their name with human interaction, which for parrots is a good thing. You will notice that parrots are most happy when they are getting attention from humans.
By raising the pitch and tone of your voice, you can get your birds into a happy state and the words you speak will have more meaning. A dull and boring low pitched voice will hinder the reception of what your bird gets. Parrots are very emotional birds and they pick up on your emotions faster then you do theirs.
Petarticles.net is dedicated to teaching everyone the importance of having a healthy relationship with their pet. Teaching your parrot tricks is time well spent that will lead to a long lasting bond.
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