they are earned, but you also can have a bird who "earns" them consistently (but then loses that privilege due to hormones or something), so you have to be SUPER in-tune with their general behavior (because that's a VERY vulnerable place to be bitten)...and they can get kind of insistent about doing things when they are used to doing them. I let my cockatoo on mine, but this is still risk (obviously). She is also an adult and I can read her really well 99% of the time, but I could still lose an eye if I didn't pay attention or missed a cue--people do get bitten on their faces by trustworthy birds from time-to-time..
I just thought of this, but because Noodles gets on mine, she thinks she can do it on everyone (and that is another potential issue if you don't teach people how to prevent it ahead of time). I am comfortable with her on the shoulder of 1-2 other people in my life, but they have also spent A TON of time with her. People are often willing to let her go on theirs and I have to pretty much block or pre-teach what you shouldn't allow for fear of her lulling them into a false sense of security lol. Shes bitten my mom's shoulder before....seemingly out of the blue to my mom. It was a sneaky move on Noodles' part, but it related to the proximity of my dad (whom Noodles wishes SHE could marry).
She has never bitten anyone on the face (well..she did get me on the cheek once, but that was TOTALLY my fault for getting her all worked up and dancing to Come on Eileen lol!), but sometimes, she will manage to get onto a less-familiar person's shoulder and resist leaving and get snippy if they try to remove her and then people get nervous. I do not have this issue, but that is why I try to prevent her from getting on other people's shoulders unless they know her very well...
When my much younger sister first was bonding with her many years ago (and I was visiting the family with the bird), they got along really well, and at the time, my sister was probably 17-ish? Anyway, Noodles was pretty good with her when I was around- didn't do much that was objectionable.. They had weeks of interaction and my sister could get her to step up easily etc. Anyway, one day, my mom and I went out for the afternoon and my sister let Noodles out of the cage (because they got along really well and Noodles gets so pathetic---she called and I was like, "if you want to let her out and you feel safe doing that, you can, but just be careful because she can get bossy"). Anyway, apparently, it was all good until she got on her shoulder and basically trapped her lol/eek! She posted some pictures of them hanging out, but like 20 minutes later, I got a crying phone-call ("when will you be home I am stuck---she won't get down and she bites at my hand whenever I try!!!")...She did end up with some bruises, but the tears were more out of frustration and panic than actual pain...as in, will I have to sit here with this tyrant for 4 hours??!!?
Not an issue these days, but I mention that because different people can have very different experiences with the same bird based on history, bonds etc...Noodles LOVED my sister, but there was a weird period of trust mixed with random pushy behavior mixed in.
I KNOOOOOOW Amazons and cockatoos are like night and day, BUT, I just mention that because it may be relevant in some way shape or form lol.
