YOUR BIGGER THAN HE IS, hahhahahahaa , LOL
Seriously sometimes we move quickly and I think it makes them fearful, especially if they have not been with us for a long time. I would say it was that he was just hungry and being grabby, but you also said he at times mouth gapes at you , which tells me he's still a little fearful.
Try to approach him low and in front of his face or off to his side but low, so he sees you coming and can get a good bite on you, NO I'm just TEASING,... You do not want to come down from the top OVER him like a preditor (large bird or whatever)would do to eat him.
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PHEve / Eve