You can, but only if you pack animals from your zoo into the storage. If the storage reach 50/50 you can no longer buy animals, or use "move to trade center" button to pack them from [1], but you still pack your zoo animals by selecting them 1 by 1 and click send to trade center under the right window.
Same as Franchise Mode, i ever had a breeding base and stored 200+/50 animals into the storage, and i used a lot of time selling / releasing animals before i clear the storage and buy new animals from the market again
***Use this button to store animals to the storage when your storage is over 50/50
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