Ages 4 to 5 years. Some dolphins live in huge pods, and others prefer to live in small groups or even alone. What do we really know about dolphin behaviour? This exciting book answers such questions as what do dolphins do all day and night?; How do dolphins learn to hunt and co-operate in catching prey?; When do they rest and how do they decide with which group they will spend their time?; Why do Hawaiian spinners travel in groups of hundreds?