That's some solid work!
Planet coaster has an assumedly older dictionary:
https://console.planetcoaster.com/planco-dictionary
Of those words, only these ones are in this Planet Coaster version:
- Cobra
- Fly (noun)
- Dinosaur
- Dragon
- Kraken
- Mouse
- Fish
- Octopus
- Parrot
- Pigeon
- Rat
- Raven
It is quite interesting that Mammoth and Unicorn seem to have been added for Planet Zoo, I'm guessing they might have been planned as scenery at one point, like the dodo.
An interesting thing to note, Secretary is missing.
All in all, it does strike me as plans of the past, but it is interesting they've been thinking about the skies and the seas at some point.