Conure behavior question
A green cheek conure was given to me last year and it had been neglected since the children it was bought for left home (17 years?). It seemed happy most of the year with a new big cage new toys and new kinds of food. It also enjoys the company of the African grey nearby. But suddenly now all it does is stay in it's furry Tube. If I get him out he acts happy eating, ringing bells, walking outside the cage on it's perch but suddenly always goes back to the tube. I replaced the tube once and put a nesting box wondering if it was some sort of nesting thing. I need advice on what to do. thanks.