Timm Spretke, deputy director of the Leipzig Zoo, said Nelson was immediately rejected by his mother, Owaka, despite being the only one of three chicks to survive hatching, The Local reported Monday.
Spretke said zoo worker Petra Strecker has been feeding Nelson for the past seven weeks with a homemade parrot-food paste but the baby bird's survival is in question.
"He's not quite out of the woods yet because he's not yet taking food himself," Spretke said.
The parrot has gained a measure of celebrity, with the newspaper Bild describing him as "a cross between a roast chicken and an alien" and Britain's Daily Mail suggesting he "could be the ugliest bird in the world."
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