In my three expeditions to Nikumaroro, I have not found the fish to be so tame as to be simply scooped out of the water by hand. No matter how tame, simply scooping fish out of water seems to me to be a pretty difficult trick, so my guess is that Maude was exaggerating a tad for effect. Maybe he was imagining using a net which would have been much easier to scoop fish with.
In 2001, there were a whole lot more fish than in the later trips - 2007 and 2010, evidently due to the rise in temperatures in the central Pacific. Even then, we couldn't have scooped them by hand. I was successful at catching a fish by hand on the reef flat at low tide, but that was only because there were three of them trapped in a hole with nowhere to go. I managed to get one by the tail and yank him out, but it didn't take long for it to squiggle out of my grasp. They are slimy buggers that fight for freedom, makes them hard to hold onto. If I'd had a spear or a net, on the other hand, I would've have had three fish for dinner.
Andrew