After the second day, you will learn that the national park is in danger of being destroyed to make room for a shopping center by evil businessmen. The animals all agree to do what they can to save the park, and that involves secret buried treasure!
Your main quest is to find all nine treasure map pieces to locate the buried treasure. Usually, map pieces are given as quest rewards, so be on the lookout for characters with exclamation marks over their heads, as this denotes a quest.