One of the founding fathers of marine mammal bioacoustics, William Watkins, carried out pioneering work with William Schevill at the Woods Hole Oceanographic Institution for more than four decades, laying the groundwork for the present day field. One of the lasting achievements of his career was the Watkins Marine Mammal Sound Database, a resource that contains approximately 2000 unique recordings of more than 60 species of marine mammals, with more than 15,000 annotated digital sound clips. These recordings have enormous historical and scientific value. They provide sounds professionally identified as produced by particular marine mammal species in defined geographic regions during specific seasons, which can be used as reference datasets for marine mammal detections from the growing amounts of passive acoustic monitoring data that are being collected worldwide. In addition, the archive contains recordings that span 7 decades, and includes the very first recordings of 51 species of marine mammals. These ...