Dolphins
Glitched dolphins appear when you have two dolphins, male and female, and at least one other animal cage that is not a sea animal. Usually when the other animals have a baby, a dolphin appears with it. The dolphin will appear to be swimming, even when on land. When you click on the dolphin, your game will freeze. However, there is one way to view the glitch dolphins heath stats. First, tap any other animal in the cage (unless there are multiple glitched dolphins, in that case tap a regular animal). Then, press the L or R until the arrow lands on the glitched dolphin. You will now be able to view its stats and go to Zookeeper mode. Note: It is best to save your game before attempting this, because the entire screen will turn black after you are done in Zookeeper mode. There is only one way to get rid of the glitched dolphins. First, build a sea animal tank. Second, try to move the glitched dolphins to the tank. Then, save the game. Finally, try to sell the glitched dolphin(s). Note: On the first try, your game will freeze.
Wrong exhibit after birth
When any animal that is in a water tank exhibit gives birth, sometimes it will have its baby in another exhibit other than one with a water tank. For example, a dolphin born in a koala exhibit.
