Quoted from EStroh:Maybe this will help:
Who goes white water rafting in the snow?
It's a Bigfoot, not a Yeti.
All the artwork in the center of the playfield, the translite, the topper, and the outside of the cabinet include brown rocks.
But hey - it's your game... do whatever floats your boat... er ... raft.
Where did the water in the river come from? The frozen tops of the mountains. Plus you can be crazy https://trr.co.nz/blog/rafting-in-winter-on-the-tongariro/