These unique birds are a symbol of wisdom and are great hunters. There are about 250 species of owls that live throughout the world. Most owls are nocturnal and spend most of their time hunting for food. Their ability to rotate their head 270 degrees is very beneficial for hunting. They are not great nest builders, so they often take advantage of using nests built by other birds. Owls are forced to move when vegetation is cleared or habitats are destroyed, meaning they have to crowd into small spaces. This limits their ability to find enough food.