Zho's Journal

If you fight Zho in The Norn Fighting Tournament (Gunnar's Hold, GW:EN) and successfully beat her, she gives you a journal chronicling her quest to hatch a Black Moa of her own, and suggests that you can follow the same steps to hatch your own black moa.

This appears to be a new type of quest: it doesn't appear in the quest log, and there are no exclamation marks over NPCs' heads, or arrows or hints in the mini-map.

Captain Juno in Cavalon sends you to Katharine to obtain an incubator for a Moa egg.