To mark World Earth Day, veteran National Geographic photojournalist Brian Skerry tells Harry Guerin about his new series Secrets of the Whales. Executive produced by James Cameron and narrated by Sigourney Weaver, Secrets of the Whales is streaming now on Disney+.

This series has a few superlatives.
It certainly was the most ambitious. In terms of my career at National Geographic Magazine, this would have been the 28th story that I did and, of course, we added this massive television series, and we're producing a book as well. To have three years to work on something is a bit unprecedented. Usually, I might get 12 or 14/15 weeks on a normal assignment that I break up over a couple of years. But this was 24 locations, three years.

Brian Skerry travels to Norway's remote fjords to document new orca behaviour (National Geographic for Disney+/Luis Lamar)

It was daunting because we were trying to 'do' whales, which can be a real challenge. It's completely on their terms; there's nothing you can do. You can't attract a whale; you can't do anything other than just be there and wait. That being said, I often say there was divine intervention along the way. I think we had some real great luck and ended up being successful in every location.

National Geographic photographer Brian Skerry documents a special orca society off the North Island of New Zealand (National Geographic for Disney+/Kina Scollay)

It really is hypnotic underwater.
As terrestrial creatures, we often see our planet from that terrestrial-centric viewpoint, I think. But we very much live on a water planet. If you look at Earth from space, you realise that we live on a very-much ocean planet. Ninety-eight per cent of the biosphere - 98% of where life can exist on Earth - is water, is ocean, yet it's very foreign to us. It's an alien place and everything is in motion - that's what I always see. I often say when I go into a place for the first time, it's chaos.

The narwhal's world may look barren from above, but the waters underneath the Arctic ice glow with life - corals, anemones, fish, and comb jellies (National Geographic for Disney+/Ernie Kovacs)

The way that I try to make pictures is to just slow it down, to just observe for a while and focus on individual scenes, and then I make order out of chaos. I did a story in Ireland - I spent 10 weeks doing a story on underwater Ireland years ago - and I was working in Valentia in the beginning. I remember the first time being down there with cuckoo wrasses or grey seals and all this stuff buzzing around. It is a bit hypnotic and a bit chaotic, but after a few dives you begin to settle in and you start to understand and make order out of it all.

National Geographic photographer Brian Skerry spent three years documenting the cultural lives of whales for Secrets of the Whales (National Geographic for Disney+/Luis Lamar)

What moved me the most on this series is just how complex, and how much like us in many ways, these whale societies are.
When I created this series, this project, I asked everybody to look at these animals through the lens of culture. This was not going to be a typical natural history, somewhat clinical documentary or project where we looked at these animals differently than us - but more like us. I had done some research - talking to researchers and reading scientific papers for the better part of the last decade - before we went into the field and was looking for a way to connect multi-species of whales. I settled on this notion of culture.

Scientists believe humpbacks breach to communicate with other whales - although it also looks like fun (National Geographic for Disney+/Hayes Baxley)

Some of the latest science is showing that, like humans, within an identical species - so whether it's orcas or sperm whales or belugas - within a genetically identical species, depending where in the world they live, they're doing things differently. So, they might like a different type of food preference. They like their own ethnic foods, or they have dialects and they isolate themselves by dialect. They don't intermingle necessarily. They have singing competitions. Even at the family level, they might have different parenting strategies and techniques. They assign different types of babysitters to watch their young. So, that was what I really went in with - hoping - and came away with even more revelations, I think, than I expected.

Orcas in New Zealand follow a unique hunting technique: taking stingrays off the bottom - sometimes in very shallow water (National Geographic for Disney+/Kina Scollay)

What surprised me most was the empathy - the love that these animals have.
For example, sperm whales. This is an animal that has historically been portrayed as a leviathan - you know, Moby Dick, Herman Melville, this kind of thing. And, of course, we know that's not accurate, necessarily. But to spend weeks or even months with these animals in multiple locations - you'll see them come together at random times and just reaffirm these family bonds.

Belugas are extremely social and have been nicknamed "the canary of the sea" because of their rich and varied vocal range (National Geographic for Disney/Peter Kragh)

These are animals that live in the deep ocean; they're mighty pelagic animals that migrate throughout the high seas, and yet every so often they come together. Animals that spend most of their lives in the deep ocean - you can imagine where they're not touching anything, they don't rest or sleep on the bottom, they're not sleeping up on a beach - come together and rub each other and bite each other and gently just spend an hour or two in this very social, loving situation.

Many sperm whales are wandering nomads. They travel freely across vast stretches of ocean and stop to interact with local whales (National Geographic for Disney+/Hayes Baxley)

Or to see an orca mom in the Norwegian Arctic one morning carrying her dead baby, her dead calf... This family of orca was very purposefully moving through a fjord and I was able to get in. It was a cold, snowy day, but I saw her with her calf draped over her head and, you know, it reminded me of a funeral procession or some type of mourning ceremony.

The humpback's tail - called a fluke - has patterns as unique as a human fingerprint. Scientists use them to identify individuals year after year (National Geographic for Disney+/Hayes Baxley)

We don't understand all of this; we don't know what happened after and so forth, but you can't help but be struck by the empathy, the love that these animals have for each other. The fact that they celebrate identity - that matters to them. Ancestral traditions matter to them. They pass these down to their offspring like humans do. They're not only teaching their young how to survive - like us, because they're not born with innate traits - but they're also teaching them about their culture. I think that's what I really took away from this.

Whales are more like us than we ever thought possible. New research show that they are deeply intelligent beings with their own distinct cultures around the globe (National Geographic for Disney+/Luis Lamar)

The hardest part of my job is the things you can't control.
Which are the animals, the weather, all of the variables. In my book Secrets of the Whales I talk about whale photography and if you did a Venn diagram, if you drew all the little circles of the things you need to get a great picture of whales. You need the whales to be there. You need calm weather. You need to be able to get out in a boat. You need the whale to be approachable. You might see them on the surface, but they might only be up for a few moments. You have to get within a hundred metres with your boat maybe and then slip into the water.

A group of humpbacks approach biologist Nan Hauser and National Geographic photographer Brian Skerry (National Geographic for Disney+/Hayes Baxley)

I'm just free diving - I'm holding my breath so I have to swim in. The whale has to let me close. The sun has to be out because if it's cloudy, there's no picture - you can't 'light' a whale underwater. They have to be facing in the sun direction. Ideally, there's more than one whale so it's interesting. Ideally, they're doing something interesting - some behaviour, some cultural behaviour. So, all of those things, if you line them up, the tiny bullseye that remains is very tiny. Inevitably, you're spending far more time at sea, on location, in the water without getting anything. But those magic moments do happen, and that's what you're looking for.

A baby beluga smiles at the camera. Belugas are the only whale that can use their lips to form different shapes to communicate (National Geographic for Disney/Peter Kragh)

I wouldn't say that I'm necessarily more optimistic about how we're treating the planet - I'm cautiously optimistic.
I started diving in the late 1970s in New England, where I live. Back then, I never saw plastic in the ocean. I don't remember ever seeing it when I was a teenager or in my twenties or thirties. But these days, on almost every dive, you see it. I go to some of the most remote islands in the world in the middle of the Central/South Pacific - these are uninhabited places that you could walk down a mile of white, sandy beach and be up to your knees almost in plastic the whole way. Eighteen billion pounds of plastic is dumped into the ocean every single year. These are things that we do have the ability to control. We can absolutely do a better job with that.

Fishing gear is the most common form of plastic pollution in the ocean, and it is often lethal to marine wildlife, including whales. The National Geographic team saved this turtle while on assignment in the Indian Ocean (National Geographic for Disney+/Hayes Baxley)

I did a story on the global fisheries crisis several years ago after a scientific paper was published that stated that 90% of the big fish in the ocean have been taken post World War II - the tuna, the billfish, the sharks. We're killing more than 100 million sharks every single year. We've lost half the world's coral reefs. The sea temperatures are rising and it's having a devastating effect on so many things in the ocean.

Beluga whales thrive in the Arctic, but they are threatened by polar bears, killer whales and now, us, as melting sea ice opens new shipping opportunities in the far north (National Geographic for Disney+/Alexander Sletten)

These whales that are wonderful ambassadors, they're at the top of the food chain so they're absorbing all of these heavy metals and toxins and PCBs [polychlorinated biphenyls - toxic industrial compounds]. The reason that orca calf likely died was because her mother passed on all these toxic chemicals through the placenta in the uterus. It's a horrible situation.

Marine biologist Asha DeVos studies a sample of sperm whale dung, which will give her clues into what the whales are eating (National Geographic for Disney+/Andrew Mitchell)

What gives me hope is that we know the solutions now.
Years ago, we didn't. But maybe for the first time in human history we're living at this pivotal moment where we understand the problems and the solutions. We just need that collective will to move towards those solutions, creating more marine-protected areas. Science says we need about 30-40% of the oceans to be protected. Today, depending how you look at it, we're somewhere between 3% and 7%. We have a long way to go. But if we do that, the ocean has the ability to heal itself - if we can stop dumping chemicals and plastics, if we can do better with CO2 emissions. These are big things, but if we can imagine it, I believe we can do it. So, that's where the hope lies.

Entanglement in marine debris, like this laundry bin, is often lethal to marine wildlife, including whales. The National Geographic team saved this sea turtle while on assignment in the Indian Ocean (National Geographic for Disney+/Luis Lamar)

I've often wondered during the last year if we as a species might be a little more empathetic in the future.
That there may be some silver linings to the pain and suffering so many have suffered this last year, in the sense that we view our world a little bit differently. I think that's what it's about. I firmly believe that there are always going to be people who have their own self-interest or greed or whatever at heart. But, by and large, if you grab a group of people anywhere in the world, most people are very reasonable. If we present the problems and the solutions for their lives, for their children's lives, they would want to do the right thing. So, I think it's about good science and good storytelling, which is what we're trying to do here. It's a race. I think the window of opportunity exists, but it's closing. So, we need to work a little harder.

Brian Skerry - Fighting the good fight (National Geographic for Disney+/Andrew Mitchell)

Secrets of the Whales is available on Disney+ from Thursday, 22 April.

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