"Wyvern chicks are very fragile at birth, although their teeth grow in quick, their scales remain a dark green colour, and are uneven, soft and pliable until after their first shed at 2-3 weeks, when they start hardening into adult scales an taking on their adult colour. This is usually the time that the chicks start venturing from the nest, gliding short distances on still-unstable wings. Some chicks are able to survive independently from 4 weeks, but most stay exclusively with their parents until 8-10 weeks, which is when the yellow around their mouth fades, and they leave the main nest, but stay nearby, catching their own food (often birds and small game). They leave the territory indefinitely once they are large enough to hunt the same food as their parents, and therefore become competition and must be driven out."

Yeah I came up with that shit while drawing the dragon :v might draw another picture with this same dragon as an adult...idk. Heh... "uneven, soft and pliable' scales..pfft just an excuse for my messy scale-drawing.
And um yeah it's got really long limbs, so that's why it looks like that arm/wing is floating. Yeah, that's the reason.