Well if you look at pictuers of male Nosy Be's taken in the wild, like in the panther chameleon book by gary ferguson, they are not all true blue. I don't know if there is a spot on the island where the males are generally always blue or not because i have never been there but I have seen more than a few wild caught Nosy Be males come in as a turqouise/greenish color with sky to deep blue bars. All I'm saying is it looks like many of the wild photographed nosy be's I have seen, my guess is that the female is most likely true blue if most of her offspring are that way but may have normal green and blue Nosy Be genetics somewhere far back that got expressed. Either way he is a very colorful little guy.
Justin