African Gray biting and interaction.

Question
My african gray won`t let me pet anymore, If i try to stroke his head he/she tries to bite. Also when i approach the cage he is very warey of me but when my wife tries the same he will come to her and put his feet through the cage etc he climbs towards my wife when she tries to stroke him.
any suggestions on the biting and gaining my birds trust.I don`t know what i might have done wrong.
thanks Mr Keith Day

Answer
Hello, This is very common among greys they will 'swich' partners after being the home so long with multiple people...meaning they will now regect a person who raised it from a baby and now only allow the other new person to care for it, You've not mentioned is your grey a congo or a timneh? Congos are much more likely to swich partners/bonds then timnehs. The only thing I can say is to not hate the bird for changing from you being his favorite and now your wife being his favorite...if you'd done research prior to getting the bird you'd note that greys offen change from loving one person to dispising them in a multi person household, Giving him his favorite treats by hand can help, holding out a favorite toy may also help, just dont ignore him now keep up with passing by his cage and saying hello good moring that sort of thing being the one to open the cage door to let him out also can't hurt... I can't help with biting but will supply an article that might be of some help:
http://www.africangreys.com/articles/behavior/biting.htm

best of luck.