If you are a true vegan, you know the central tenant of veganism is to not exploit animals. Everything else builds on that central idea. Therefore, the fact that the animal park practices conservationism is the very reason you would not support, and not a reason to support it, as you seem to think.
You are either a vegan or you are not. If you are a vegan you do not support anything that exploits animals, not even conserving them, rescuing them, helping them. If you believe in rescuing animals or you own a pet, you exploit animals. As such, you may rightly call yourself an animal lover, but not a vegan.
Choose for yourself.