 Little was known about parrot-diet in the 1700s, and the Vienna specimen may not have received enough of the amino acid tyrosine through its food, which it would have needed for melanin synthesis.In other parrots, this would have resulted in orange instead of white colour in the affected feathers, due to the presence of the pigment psittacin, but "Coracopsis" parrots and the Mascarene parrot are the only parrots that lack this pigment.The specimen has also been described as "partially albinistic" at times, though true albinism (lack of the enzyme tyrosinase) can by definition never only be partial.