Secret Killers of Monterey

Join marine biologist Nancy Black on a journey into the world of one of the ocean's top predators. Her aim is to capture the essence of killer whales and the extraordinary tactics they use to hunt their prey. Killer whales can be fierce nomadic hunters and in Monterey Bay, California, groups hunt massive grey whales - that is if they can find one. Monterey Bay, off the central coast of California, is the largest marine sanctuary in the United States. Marine biologist, Nancy Black is here to film a distinct group of killer whales, known as 'transients', who prowl the west coast of North America in search of warm-blooded prey. Their way of life is focused on the hunt, feeding almost exclusively on mammals such as seals, porpoises and whales. They are the masters of surprise attacks, and can eat up to 200lbs of food per day. But this year, unusual things are happening in Monterey Bay. The grey whale population is down and some of these individuals are starving. What's more, a pod of resident killer whales from the Pacific Northwest have turned up in the Bay - further south than they've ever been seen before. Something is definitely wrong. National Geographic's SECRET KILLERS OF MONTEREY BAY is a film that sets out to record the behavioral patterns of a unique species of killer whales, but ends up discovering that we are in very real danger of losing these magnificent animals forever.