At the end of the day I believe it mostly comes down to who is the Director at the time one good example was the late great John Kelly of Taronga zoo under his leadership we saw a whole Gorilla troop of ten imported from Holland and a large group of wild caught Black rhinos imported from Africa. Unlike the short sightedness of the Thai elephant import of cramping them up in a city zoo at great cost only to relocate them again at cost to Dubbo to give then the room they needed in the first place.
Monarto's Director that retired, whose name escapes me at the moment. She is/ was also a fantastic director to developing the zoo. She had. good mix of developing the human amenities the zoo needed but balanced out by new species, new exhibits and growth in the overall species and holdings.