The hippocampus is critical for forming instantaneous (one-shot) memories. What happens in the hippocampus at moments of memory storage and recall? We have developed a strategy to address this question – recording the hippocampus of memory expert birds from the food-caching chickadee family. These birds prolifically hide food items in scattered locations, then return later to retrieve food using memory. We have recorded, using calcium imaging, large populations of neurons from the hippocampus during bouts of food caching and retrieving. I will present evidence for transient memory-related activity in the hippocampus, and reactivation of cache-related activity patterns preceding moments of food retrieval. I will compare this transient memory-related activity to sustained changes in hippocampal activity that have been described to occur near locations where an animal consistently receives reward. Finally, I will relate these two modes of hippocampal activity in the context of a predictive model of hippocampus function.