'Planet Earth III': Surprising way humpback whales in Vancouver Island help to restore the ecosystem

For the popular, breathtaking docuseries, BBC Earth's Planet Earth III, narrated by Sir David Attenborough, producer and director Dr. Fredi Devas spent two years capturing amazing footage of humpback whales trap-feeding in British Columbia.

The eight-part season, the latest addition to the series that premiered almost 20 years ago, continues to push the boundaries and innovate how we're able to film all elements of the natural world.

"I think what we did in [Planet Earth], the team back then really gave a new perspective on the natural world, and that was from this stabilized camera, mounted on a helicopter, where you could see wildlife spectacles for the first time, really the scale of them for the first time," Devas told Yahoo Canada. "Then for Planet Earth II, we really wanted to give a more intimate portrayal of the animal world, so we had these stabilized cameras, but handheld, and we were able to capture the animals from their level, with their perspective."

"On Planet Earth III we thought, well how do we bring it up to date? And we thought, well let's take both of those, aerial perspective and intimate portrayal, but really bring it up to date and talk about the state of the natural world right now. Because we are facing some really dire environmental problems, but the natural world is still so beautiful to see, and so why not just talk about how special it is, and the really immediate need to protect it."

How humpback whales sequester carbon to help restore our ecosystem

Episode 7 of Planet Earth III, titled "Human," features Vancouver Island, and it's a particularly hopeful story about animals adapting to how the natural world has changed.

"The story of humpback whales in Vancouver is such a positive one, because it's where humans have turned it around," Devas highlighted. "They were whaling these great whales almost to extinction and then the ban on the commercial hunting came in 1986, and since then we've slowly started to see a number of great whale populations start to increase."

"One of those is the humpback whales who visit Telegraph Cove on Vancouver Island."

Devas added that a scientist he worked with, Jackie Hildering, stressed that 20 years ago she saw three humpback whales in one season, but now she's seen over 100 coming to these waters.

For the series, Devas wanted to capture the trap-feeding behaviour of the whales, which is seen nowhere else in the world, but he also wanted to show the audience that, quite literally, their poo is helping to restore the entire ecosystem, specifically by sequestering carbon, and on a "massive" scale.

"Each humpback whale is equivalent to about 30,000 trees for the amount of carbon it sequesters out of the atmosphere," Devas said.

He added that is was "very difficult" to capture this trap-feeding, in the first year they didn't capture it at all, having to wait for the second year. Devas also stressed it's becoming "essential" to be given the time and resources to capture these animal behaviours, as climate change continues.

"So what happened in our first year, the humpback whales were all there, the herring were there, you would expect the trap feeding to happen," he explained. "We'd studied the scientific literature, we were with the scientists that had studied the behaviour, we had everything right in place, but the truth is very little trap feeding happened that year."

"That's because there was a huge influx of these short-tailed shearwater birds. There's normally around 3,000 in the area at that time, but some ornithologists think there may be as many as 40,000 that came that year. They didn't come the year after, they didn't come the year before, they haven't come since. So the question is, why? Where did they come from? ... Climate change is having a massive impact on animal behaviour."

With respect to climate change, after a short break from filming in B.C., Devas went to the Amazon in Brazil, which resulted in a particularly difficult shoot, to film the rainforest fires.

"That was by far the most difficult shoot I've ever done in my life," Devas said. "It was difficult because we spent a month documenting the burning fires in the Amazon and I was, I think, emotionally prepared for the first fire."

"But I wasn't prepared for finishing that day's filming and waking up the next day and going, right what are we doing today? We're going to go and find another fire and another fire, and another fire, and doing that for a month. I think that was really, really difficult to witness, as well as being extremely challenging, because when you're filming around fires, it's incredibly hot. There's a ridiculous amount of smoke, it's dangerous, and you have to be very, very prepared and take health and safety very seriously, which we did. Everything went according to plan, everyone was fine, but that was a very challenging shoot."

'Nature is not something that is nice to have'

For any who watching Planet Earth III, Devas hopes to spread the message that the state of the natural world right now is something that needs our attention.

"Nature is not something that is nice to have, it's something that's essential for life on this planet, and that's our life as well," he stressed.

"When you look at the surveys of how important people think the natural world is, it's regularly 80 to 90 per cent of people think it's eight, nine or 10 out of 10, it's hugely important. So people care about wildlife, that's clear. People love wildlife, that's clear. I think what we need is for certain powers, certain people with huge responsibility, to really start prioritizing the long term future of the natural world over other priorities, like profits. I think that's what's really important."

Planet Earth III premiered Sunday, March 10 at 9:00 p.m. ET/PT on BBC Earth in Canada, during the channel’s nationwide free preview event, from Feb. 26 to April 28. Episode 7 titled "Human" will air on April 21.