Blue whales are the largest animals to ever live on earth, yet they are difficult to find or track. Even some of the locations where they birth their young are great secrets. Join some of the world's eminent blue whale scientists as they embark on a revolutionary mission to identify and tag California blue whales as they migrate to a spot known as the Costa Rica Dome. This incredible voyage yields unforgettable new footage and insight into these amazing creatures' lives. Scientists use DNA analysis, recordings of whale songs, homing devices, and sea dives to shed light on the blue whale's breeding and birthing habits

The Sea of Cortez, also known as the Gulf of California, is a unique corner of the Pacific Ocean. This remarkable young sea is thought to be around five million years old and home to nearly 900 species of fish and the widest variety of whales and dolphins found anywhere on Earth. Some of the greatest changes threatening the world's oceans today can be seen in this stretch of water.

Sir David Attenborough reveals the findings of one of the most ambitious scientific studies of our time - an investigation into what is happening to our oceans. He looks at whether it is too late to save their remarkable biodiversity. Attenborough explores some of the ways in which we are affecting marine life - from over-fishing to the acidification of sea water. The film also uncovers the disturbing story of how shipping noise is deafening whales and dolphins, affecting their survival in the future.

Hunger at Sea follows blue whales, sharks, sea lions, frigatebirds, dolphins and albatrosses to reveal the strategies they use to hunt for prey in the big blue. The open ocean is an immense wilderness that covers more than half the surface of our planet, yet for the most part it's a watery desert, largely devoid of life. Predators face an endless search to find and catch food, yet these great tracts of ocean are home to some of the most remarkable hunters on the planet.

The coast is the dynamic border between land and sea; powered by the tides and thrashed by waves, this is a world of continuous change. Opportunities never last long here, so hunters are always in a race against time. The coast is the only place on the planet where predators from air, land and sea come together. Dolphins that leave the safety of the sea to fish, walking octopuses, ingenious monkeys, fishing wolves and the greatest gathering of feeding humpback whales come to the coast to hunt. For all, timing is everything.

The final episode of the series visits the frontline of the conflict with the world's top predators, meeting the scientists fighting to save them. Crossing five continents and combining landmark natural history footage with real-life human drama, it checks the pulse of the earth's iconic animals, including lions, tigers, polar bears and blue whales. With three-quarters of the planet's carnivores now in decline, can people find ways to live with predators before they disappear forever?