Here is the full list of all 12 Zoo 2: Animal Park achievements.
Have 20 employees
Have 50 visitors
Reach level 30
Have 20 different animal species
Breed 20 baby animals
Have 20 sales stalls
Open 50 treasure chests
Help 100 friends
Have 5 legendary animals
Have 200 plants
Give the baby panda a new home
Have 5 visitors in your zoo