Blue Planet III producer: "Attenborough seems stronger and better with every project"

A humpback whale breaches off New York, silhouetted against Manhattan’s towers. In Western Australia, bottlenose dolphins trap fish with sea sponges. Swarms of tiny Smith’s swimming crabs drift across the Indian Ocean, while four-metre bluefin tuna race through Cornish waters.

Such spectacular footage marks the return of the BBC’s unrivalled exploration of the world’s oceans. Four years in the making, Blue Planet III comprises six episodes packed with astonishing underwater sequences, many filmed for television for the first time. “Almost every story features a new behaviour or species,” says Lara Bickerton, series producer of Tropical Seas, Open Ocean and Seasonal Seas.

Advances in technology have made some of these scenes possible. Drone footage follows a bowhead whale using its reinforced skull to break through Arctic pack ice — one of the year’s most enthralling television moments. New deep-sea cameras also capture recently discovered species as far as 4,000 metres down, beyond the reach of sunlight.

Technology does not replace “old-fashioned fieldcraft: reading the environment and animals, and drawing on local knowledge”, says James Brickell, producer of the final three episodes, including Polar Waters. Ocean trenches and open seas are dangerous, but so are Svalbard’s Arctic shores, where the crew filmed young polar bears hunting harbour seals. “Polar bears are among the few predators that deliberately target humans,” Brickell notes.

For the film-makers, the risks are worthwhile. Many have spent years hoping to work on the series. “I grew up on the Dorset coast loving the sea,” says Bickerton. “I became a diving instructor, applied for Blue Planet II and didn’t get the job. Now I’m finally working on Blue Planet III and still have to pinch myself.”

Working with Sir David Attenborough brought another thrill. “He’s an icon. When he read his opening line in the studio, the producer and I looked at each other and burst into tears. We knew we were part of a special moment.”

“Attenborough seems stronger and better with every project,” says executive producer Elizabeth White. “His engagement astonished me — his humour, personality and love for the programme. He retains such curiosity and wonder. When we showed him newly filmed behaviour, including the bottlenose dolphin and millions of Smith’s swimming crabs gathering, he was like an excited boy.”

Nine years ago, Blue Planet II confronted viewers with whales and turtles entangled in plastic and abandoned fishing nets, effectively declaring an ocean emergency. The series reportedly reached 500 million people worldwide and helped spur international action. In 2019, 170 countries at the UN Environment Assembly agreed to “significantly reduce” single-use plastics by 2030 — a response dubbed the Blue Planet effect.

Since then, global warming has intensified and further threats have emerged. Svalbard’s polar bears now hunt along the shore because the ice is inaccessible. As the polar cap melts, the Labrador Current – which carries nutrient-rich cold water down North America’s eastern seaboard – is also weakening. In Maine, puffins face starvation as their main prey, sand eels, disappears.

Rising temperatures affect every ocean. Bleaching on the Great Barrier Reef kills coral and the anemones that shelter clownfish, the orange-and-white species popularised by Finding Nemo. Yet Blue Planet III remains hopeful: many featured animals are thriving or adapting. Clownfish, for example, have begun cleaning their anemones to help keep them alive.

“We deliberately avoided a sense of doom,” says White. “Showing adaptation is honest: some animals are adjusting, and in protected ocean areas populations are returning.” That may be the series’ strongest message. “Humpback whales are breaching off New York because fisheries have recovered,” she says. “Fishing practices changed and the animals returned. There are many stories of hope.”

Blue Planet III is on Sunday 1 November at 8pm on BBC One.

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