My bird humps, eats regurgitation, and hangs upside down. Why?

This may be mating or sexual behavior. The whole seed indicates regurgitation instead of vomiting. The rubbing of the perch is likely mounting behavior. It should pass. You can provide different toys or rearrange the cage to distract him, but there is no cause for concern as long as he is behaving normally otherwise.

Regurgitation can be a sign of affection/wanting to mate, and some birds may display this behavior toward people they are bonded with if they do not have a mate. It is best to discourage the behavior by either stopping interactions when it happens, or distracting with a favorite toy or treat instead. Puzzle toys or things that can be chewed on/groomed may help him get out some boredom or affection for the object instead.

It's always difficult to assess any animals level of happiness, but I can definitely tell you that this bird does not seem unhappy. The humping and regurgitation (puking) tell me that Toetie is very comfortable in his environment and has formed a bond with you. Also, he appears rather healthy from the pictures you've submitted. I think the most important things to keep a bird happy are supplying good enrichment and as much space as you can possibly give. Enrichment can be as simple as letting the bird out of the cage, interacting with the bird, or giving toys. I understand that he does not seem to be interested in toys, so it may take some experimenting to find out which ones he may like. I have found that the best enrichment can be achieved by making the bird work for its food. There are plenty of toys for sale that you can hide food in and the bird has to either solve a puzzle or dismantle it to get the prize. I used to feed my parrot most of his food this way and it really helped to keep him from getting too bored when I was away during the day. This website looks to have many great ideas for bird enrichment: http://www.birdsnways.com/birds/iedible.htm Another enrichment idea is getting Toetie a mate of the same species. This is not easy, because you would have to ensure they get along before putting them together. Also, you should understand that a bird will always prefer the company of another bird, rather than a human. So, giving him a mate may make him less likely to interact with you or other people. I hope this helps and at least gives you peace-of-mind that Toetie is at least not depressed.

It isn't common, but it can happen. If it happens again, ignore the behavior or gently distract him with a toy or piece of food. Avoid petting or scratching his back or under the wings and do not "beak wrestle" with him. These are all courting behaviors.

He may simply be playing and having fun. If he is doing it all the time, he may be stressed or bored. Try rearranging the perches and switching old toys for new ones to freshen up his environment. Spend more time with him outside of the cage if possible. When he exhibits the behavior distract him with toys or treats then reward and praise him when he responds to you.

Birds can sometimes begin to regurgitate or share food if they're feeling in a "lovey" or mating mood. It may be that he is considering you a potential mate. It'd be best not to encourage the behavior if this is the case, and to try and interact with him in other ways, such as offering a toy to play with, walking away when he attempts it etc. If you're seeing any other symptoms such as changes in eating habits, stool changes, listless behavior, etc, then it could indicate something beyond just behavioral, and scheduling a vet checkup is always a good idea.

Have Sky examined by your veterinarian or an experienced avian vet to diagnose illness or injury. You can also move the cage away from direct sunlight and limit daylight hours using a cage cover. This may stop his mating behavior if that is what it is. Limit any interaction, such as beak wrestling, that may foster mating behavior as well.