Bird shit drops on the ground occasionally, implying the existence of (potentially invisible) birds. Also the sea monster and fish. Burgers, hot dogs and chinese food exist, meaning cows and pigs could exist as well.
There is a polar bear doll, buyable deer antlers, a cat cafe, rubber ducks, and the Paralake flag has a platypus on it. In-universe, they should all exist, though it is probably safe to assume Paralake is set in the real world, so all others would exist too.
There is also a fly in the bunker!