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make sure they have plenty of room. Give them all the toys and the best houses. assign a keeper to just their area. Make sure they don't have a dirty area outside the fence. (one of my bears get mad every time someone throws something on the ground outside of his fence). Also make sure they aren't by another animal they don't like. Some of my smaller animals were a bit happier when i moved them away from my leopards even though they were in separate cages. I don't know what else to tell u. hope this helped a little. Good Luck!!