Green iguana in boat

I don't understand this setup at all. Setting aside how tiny that enclosure is, how it has no climbing structures, etc... what exactly keeps the iguana in that enclosure? And what keeps it from biting or tail-whipping someone standing next to it?

@Coelacanth18 honestly, I have no idea. It was really strange, it seems as if it could simply walk out. All of the iguanas I have known would have done so.

Absolutely terrible. It seems like the ledges keep him in, as he probably won't risk the fall, even though it isn't that tall