There are a lot of body languages/behaviours that you must decifer in order to grow trust and bond with your bird.

Here I will cover a few of the most common.

Beak grinding: Beak grinding is natural and normal. It is a sign of contentment or sleepiness. Although some people find this noise grating on the ears, you should be proud - you have a happy bird!

Head bobbing: When we first see a bird bobbing his head rapidly with his beak wide open, it can appear quite alarming! This is your birds way of showing you affection. He is motioning to regurgitate which is the highest of praise indeed! Occasionally he will actually bring some food up for you to share. Try to act in a gracious manner before you so callously mop it up!!! Regurgitating is NOT to be confused with vomiting. Vomiting in birds is rare and a sign of serious illness. Vomiting is characterised with the head shaking uncontrollably from side to side rather than up and down.

Moving rapidly from side to side on a surface such as a perch: Your bird is feeling playful and happy! Try "dancing" with him in unison. There is no greater privilege to a bird than you mimicking his happy movements!

Wing stretching: Smaller birds such as conures, meyers and senegals will often spread one wing out wide, shrug, and then spread the other. This usually happens when their favourite human/s enter the room and is a greeting of love!

Wing flipping: If your bird tends to flap his closed wings in the manner not dissimilar to us doing a chicken impression when you enter a room, he wants you to stroke him/be with you or have you pay him some attention!

Lifting a foot up to a nearby human: Birds well versed in "step up" will often motion to be picked up in this manner.

Shaking: If a bird is sitting puffed up with one foot underneath him, he is going for a nap. If the bird is sitting low with both feet grounded and puffed up, shaking, he is cold or ill. If warming the room doesn't bring almost instant results, a trip to the avian vet is on the cards. Birds hide their illness' very well and any unusual change of behaviour is worth getting checked out. Shaking with no puffing generally means your bird is afraid of something and he will most likely be clinging to the side of his cage at this point. When you remove the cause of distress he should return back to normal very quickly.

Plucking feathers: Feather plucking should not be confused with preening or moulting. If the two are occuring at once, the chances are your bird has simply removed a feather ready to fall. If a bald patch appears anywhere and there is no sign of mites/a chemical being spilt on that area for example then your bird may well be plucking.

Plucking is usually caused by stress or boredom. Parrots who have lots of company, lots of out of cage time, lots of varied toys and a good diet/sleep pattern should not pluck. If you feel you meet your birds criteria's then a trip to the vet is vital as plucking CAN be caused by illness.

If you have taken in an older bird who is a plucker or a self mutilator, here is an article from Parrot magazine that I found most useful. I have paraphrased it here.

Again, researching by means of a good species specific book, studying your bird and more often than not adjusting YOUR behaviour is the key to solving most birdy issues.