A lot of exotic birds are pretty intelligent and can probably have their needs met enough to where not being able to fly outdoors is a negligible drawback. If they have a stimulating, social and play life, I believe they can have happy good lives, even if they don't get to fly freely outside. Because with that type of intelligence, adaption to happiness tend to be possible- meaning they are able to adopt to other activities/ stimuli as main factor of happiness/ thriving (not that flying is necessarily the main thing regardless)
Problem is a lot of bird owners keep them in their cage like 23 of 24 hours, which I'd say is not a good life for most birds, unless their cage is like its own house or something. Higs' birds seems to have pretty good lives, though, so don't think you need to feel guilty about them.
Not being able to fly outside might have the biggest drawback for bigger birds. But a lot of the bigger parrots also very easily starts plucking their feathers when they are unhappy, and a lot of parrots don't do that even when they don't get to experience free flying. I think that's an indicator that also bigger parrots don't necessarily need free flying as a part of their lives to thrive. I guess it might be partly a "what they don't know" thing.
That being said, my knowledge of parrots/ exotic birds is limited, so I wont hard press that I'm right on this one. Though, I do think if you start becoming observant of your pet and understand the signals/ body language/ etc, you can tell whether it's thriving or not to a larger degree.
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I have a "problem" when it comes to my own pets as well, as I have cats (or I guess cat, since one of them is old and stays inside most of the time), that hunt and kill small birds which is a bad thing, both ecosystemily and also because I dislike animals being killed when it can be avoided. Having them put down is a bit extreme, I think most people would consider that crazy (?). Giving them away wouldn't change anything as they'd still kill birds at their new home. So I have no plans of getting rid of them. I wasn't conscious of that when I got them, so tough luck for me. And the ecosystem.
I can also tell a lot from observing the behavior of my cats. Which is kinda interesting if you're interested in erm animal... "psychology" (????). A lot of animals are def more than just instinct machines, so to speak. Though, I guess I'm getting too far out of topic so. The End.
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As for the OP, I already took DNA from pnb, rb and rook and have their virtual clones living in a virtual simulation in my basement, those are all the pets I need
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