We had exactly such a thread just a very short while back. Easily strong enough to move such a floor board would be a tokay.; I would then expect you see his largish droppings and hear its typicall territorial calls very soon. I would then, however, also expect your roof to have an opening somewhere else, so that this animal would come and go normally through there. Stilts and vertical walls are, of course, no obstacle for such an animal. Other signs you have a tokay in the house: no more of the small rock geckos, which you should normally have in droves. The board looks large enough, that you cold stick your head, or at leats a hand up there to either see or feel, if such droppings exist. Careful, these roof spaces qare also home to centipedes, you do not want to touch one of those!
