The team also succeeds in their bold mission to confirm three whale behaviours never witnessed before at the Costa Rica Dome – courtship, calving and winter feeding. Learning more about this secret spot, they win a huge victory towards protecting the creatures and their most vital habitat. The team confirms that calves have been born at the Dome, and they confirm that blues feed all year round in this location – a behaviour never before observed in blue whales here. Previously, scientists had suspected that blue whales fed here during the winter months, but were never able to prove it.

Today, our oceans are busier and noisier, and resources the whales depend on are disappearing. And while blue whale hunting is now illegal, they remain under assault by another killer – huge, ocean-going cargo vessels. Blues have been known to become victims of ship strikes on occasion, but the numbers of fatalities have increased. In fact, the four dead blue whales found in one month during the making of this film were apparently killed by ship strikes. Whale experts worry that the amount of industrial noise in today’s oceans might play a role in their deaths.

In an earlier examination of Japanese fish markets profiled in the film, geneticists find blue whale meat for sale, despite an international ban on hunting the endangered species. And, in a surprising twist, geneticists also find that a blue whale has mated with a fin whale, resulting in a whale hybrid. Whale hybrids are rare and scientists hypothesize that this breeding behaviour may be caused by shrinking whale populations.

With stunning underwater cinematography, CGI of the whale’s internal body, high resolution maps, satellite imaging we insight from experts all help tell this new chapter in the story of the blue whale. Using National Geographic’s cutting-edge Crittercam®, which attaches to the whale’s back with suction, this special also features footage from the whale’s perspective.