Gray seals and white sharks historically inhabited Cape Cod waters hundreds of years ago. With the implementation of bounties on seal pelts, gray and harbor seal populations were decimated in Southern New England. With the loss of their preferred food source, the gray seal, white sharks disappeared from this area. With the enactment of the Marine Mammal Protection Act of 1972, seal populations have expanded southward at an ever increasing rate. Scientists now estimate the gray seal population to be around 400,000 animals in the Northwest Atlantic. With this dramatic increase of the herd population, large apex predators such as the white shark are returning in greater numbers every year. Follow seal researchers as they study gray seal life history, mating habits, density, and disease, along with the widely publicized interactions with the great white shark.