waruikazi
Legendary
You see herein lies the problem. I don't count a continent as a specific area.
There may be a large area that Greys do not occur in. However, the definition of endemic states that it must occur only in a specific area. It does not state that the species must cover all of the area entirely, but it must not occur outside of that area.
If the area we are referring to is Australia, then they would be classified as endemic.
Disclaimer: I only think all of the above, but do not know..could certainly be wrong.