Birds are becoming popular as pets,but unlike owners with more common pets,owners of birds are often not familiar with the behavioural patterns(行为模式) of the animal which allow them to recognise what the pet needs and wants.For example,most of us can recognise the behaviour a dog exhibits when he is hungry or wants attention,but how many of us know how birds go about showing the same feelings?
By learning about the behavioural patterns of the bird,his owner can forge a stronger relationship with the pet.Owners can learn how to read birds' body language,including movements of the eyes, wings, tail and beak(喙).In addition,the sounds the bird makes can also show the mood,desires,and requirements of the pet.
A bird's eyes are different from a human's.While both birds and humans have pupils(瞳孔) and irises (虹膜), birds have the ability to control the size of their pupils by enlarging and reducing their irises quickly.This behaviour,flashing,is something birds may do when they are angry,interested,or frightened.
A bird also communicates through the use of his wings.A bird may lift or open his wings as a sign of happiness.But if the bird starts opening and closing his wings,it may signal anger or pain.If a bird fails to fold his wings against his body,and instead lets them hang by his sides,the bird may be ill.Healthy adult birds will typically tuck（折起） their wings against their bodies when they are at rest.
Birds often use their tail feathers to communicate,so an understanding of this behaviour will help the pet's owner. A bird may move his tail from side to side,called wagging,to express happiness (similar to dogs in behaviour and meaning).Happiness is also the emotion expressed by other kinds of tail movements,such as moving up and down.However,if a bird fans his tail feathers out,it is usually a way to show anger or aggression.
