Whales are iconic ocean animals that hold special places in the hearts of many—and are a critical link in the structure of healthy marine ecosystems. Our research team has developed tools and novel approaches to studying the underwater lives of these ocean giants. New information on how much food whales consume allows us to calculate the amount of nutrients that they then recycle, promoting primary production and growth of vital components of the food web. This knowledge—when combined with information on where the critical foraging areas are for whales—provides the foundation for the development of marine protected areas that minimize the impacts of human activities.