It’s the images you don’t want to see — the ones that make you want to turn the page — that are most important to Steve Winter.

The career National Geographic photographer, a past recipient of the UK Natural History Museum’s Wildlife Photographer of the Year top honour — and a nominee again this past year, in the environmental awareness category — doesn’t see his role so much as inspiring a love for nature as galvanizing people to action. And as much as his photos of tiger moms playing with their cubs have moved a generation of National Geographic readers over his 35-year-plus career as a cameraman specializing in big cats in the wild, he sees his role now as warning the world that planet Earth’s remaining wild cats — all of them — are in serious trouble.

Winter’s pioneering work with jaguars in the jungles and riverine rainforests of Brazil — he was the first staff photographer in National Geographic history to do a photo essay for the magazine on the world’s third-largest and arguably most elusive big cat — is on full display in NatGeo’s December, 2017 issue, in an article headed “Kingdom of the Jaguar.”

Winter didn’t want the article to be another photo essay on the natural history of South America’s most elusive jungle predator but rather a carefully researched treatise on the threats faced by jaguars in the wild, from development projects to poaching, and the effect the jaguar’s population crash is having on local indigenous culture and heritage.

In a wide-ranging, exclusive sit-down conversation this past summer in Los Angeles, Winter — fresh off a plane from Peru — explained that while he appreciates Sir David Attenborough’s assessment during a 60 Minutes interview that nobody wants to be told the world is going to hell and it’s all their fault, it’s time for all of us realize what’s happening behind the camera on all those pretty pictures.

“I believe you have to find a way to show the reality that these animals are living,” Winter said. “Because that narrow view of a mouse jumping around on a blade of grass that I just saw on Planet Earth II yesterday is just that — a narrow view of that animal’s world. But beyond that, the world could be different.”

As an example, Winter cited his photography of tigers in the wild, a lifelong project that has seen him visit most of India and Nepal’s major wildlife parks over a 30-year period.

“I’m doing tigers,” he recalled, “and I keep hearing about Tadoba, Tadoba, Tadoba. Taboba Tiger Reserve. So, I see pictures of Tadoba. And they’re regular old tiger pictures, nothing unusual.

“Then, one day, I’m driving up to the park gate and I’m surrounded by the biggest coal mine I’ve ever seen in my life. Open pit. And at the edge of that coal mine is the beginning of this tiger reserve. Now that tiger reserve is under direct threat because of the coal mine — but I’ve never, ever seen a photograph of it.

“So I go in, take pictures, then we do a video for Nat Geo, and I go in again. No one questions me because I’m a westerner. I stand on top of a rise, wait for these giant trucks to come by with tires as big as this ceiling.

“I feel that that’s important, because you have to understand that all the protected areas in India lie on top of these coal reserves and they have a new prime minister, Manmohan Singh Narendra Modi, who would like to go in and take that.

“Now if you don’t realize the extent of that, that if you walk back not that far from the border of the park you’d fall into one of the biggest mine pits I’ve ever seen — if you don’t know that exists — then you can’t put those two things together. This reserve is under threat, and that’s important because this is the stronghold, the foundation for all the other wild tigers on the face of the earth.

“By telling people about that, you’re not beating anybody over the head. You’re just showing people the reality of the situation. We have problems. We also have solutions. I’m one of the most positive guys on the face of the earth. But I do not believe that if I just showed you these pristine tiger families and their cubs, without telling you about the other issues, I’m not doing my job. The story that needs to be told about tigers is completely different than any story we’ve heard. That was a long answer, but, you know, it’s important that people know this. “

Winter began his career as a traditional photojournalist, covering the world’s hot spots and recording the remains of vanishing cultures. He came to nature photography late in life; he estimates he didn’t see his first big cat in the wild until he was in his early 30s. Interestingly enough, given the subject matter of his photo essay for this month’s National Geographic, that cat turned out to be a jaguar. And a black jaguar at that, that scratched at his screen door late one night while he was overnighting in the rainforests of Guatemala.

It was a very different animal, though, in a very different part of the world, that made him realize the power of those disturbing photos that make you want to turn the page.

“The pictures you don’t want to look at are very important,” Winter said. “Those are the images that have done more in my career than any other. Because I saw how they propelled people to action.

“The best example I can think of, from early in my career, was when I did a story on the Kamchatka bears. We were invited by this outfitter to come to this hunting camp in Alaska. They were losing all these 14-, 15-foot bears. The guy knew why; I just don’t think he wanted to admit it. It was because they had a guaranteed hunt, which means nobody would leave without a dead bear. A bear trophy. Obviously, they were killing everything, including young females.

“I had a picture of all these skinned bears, the heads sitting in the snow, with bare teeth, skinned heads. It couldn’t have been more gross. The heads were getting ready to go into the hot springs, which would get all the dead meat off, leaving a perfectly clean skull, courtesy of mother nature.

“Well, right off the bat, that project got a hundred grand. It turns out each hunting outfit was counting each bear three times. So they thought they had three times more bears than they actually had.

“I saw then that the pictures that make people want to turn the page actually brought about more change for that specific species than any of the pretty pictures that I could have gotten.”

Winter’s most famous image — by far — was of a wild mountain lion living literally in the Hollywood Hills, surrounded by a metropolitan area of some 10 million residents. Winter used a camera trap, a technique he pioneered decades earlier while doing a story on the elusive snow leopard in the mountains of Nepal.

“The photo of the Hollywood cougar galvanized the people of LA,” Winter recalled. “The image on the front page of the LA Times excited people. It made them realize they live in such a huge metropolitan area, and yet there is actually a mountain lion in an eight-square-mile park.

“There were maybe only five people who’d truly ever seen that cat with their own eyes, and yet there are 10 million visitors a year to that park. That really woke people up.”

In a post later this week, Winter expounds on what makes a great photograph; on how camera traps changed the game, both for him personally and for conservation photography in general; on when he felt most awkward while on the job; on what it feels like to return to civilization after weeks and even months in the wilderness; on what National Geographic meant to him growing up as a small boy in rural Indiana, and what the society has brought to the world today; on the special challenges posed by jaguars; and why he now considers the lecture circuit to be his greatest calling.

©Steve Winter/Finalist, NHM Wildlife Photographer of the Year, 2017.

“Pictures that you don’t want to look at sometimes have more power,“ Winters said in a 2014 promo reel for National Geographic. “I mean, beauty’s one thing. Heartbreak is another. Pictures that you just can’t stand looking at are the ones that maybe have the most power.”

Winter’s latest nature film, Jaguar vs. Croc, anchors National Geographic Channel’s “Big Cat Week,” premiering Dec. 10 at 9/8c.

Of all the hours that went into making Planet Earth II, it is the final episode “Cities” — which makes its North American debut this weekend on BBC America — which drew the most attention when it aired in the UK last December, and small wonder.

The finale is not just a summing-up of all that has come before. It takes on the thorny issue of where the planet goes from here, as wild animals evolve and adapt — with varying degrees of success — to the world’s sprawling and ever-growing urban areas.

No spoilers here. One of the special joys in watching Planet Earth is being surprised by those unexpected moments that evoke awe, majesty and, in many cases, an almost childlike sense of wonder. Nature is full of mysteries, after all. For every answer, new questions are almost certain to emerge.

©Steve Winter, National Geographic/NatGeo Wild

The issue of how wildlife can adapt to big cities has been tackled before, most notably in National Geographic’s 2015 documentary program Urban Jungle. This is the first time the Planet Earth team have tackled it head-on, though, after almost 20 hours of often breath-taking filmmaking.

That’s worth noting because if Sir David Attenborough and his team of filmmakers have faced one criticism over the years, it’s that, for all Planet Earth’s celebration of nature at its most pure and pristine, it has pointedly avoided the ways in which human beings have affected what remains of the natural world, whether through climate change or unchecked population growth and our increasingly unsustainable lifestyles.

Evolution is not so much about survival of the fittest as it is about adaptability to ever-changing surroundings, so a close-up look at how wild animals find new ways to survive when living in close proximity to large numbers of people is ideally suited to a program with the ambition and scope of Planet Earth, and a fitting way to end the series.

Veteran National Geographic photographer Steve Winter, who followed leopards hunting by night in the centre of Mumbai and who has just concluded a multi-year photographic survey of wild jaguars in Brazil’s Pantanal region (a National Geographic magazine feature and feature-length nature documentary are in the works), shared his experience of photographing leopards — an unpredictable and potentially deadly predator — withjournalists from the Television Critics Association at a gathering in Beverly Hills, Calif. several years ago, while promoting Urban Jungle.

Coincidentally, one of Winter’s most famous photographs — of a wild mountain lion, dubbed “P22” by local biologists, living in the Hollywood Hills, the giant “Hollywood” sign lit up in the background — was taken at night using a trap camera, just a short drive from the very Beverly Hills hotel where Winter was meeting journalists.

“The leopards in Mumbai are absolutely incredible,” Winter recalled. “They come out when it gets dark. People live right on the edge of the park. I was there, and saw it with my own eyes. People would do their walking, exercising, walk their dogs like we do in parks, and, boom, the sun goes down, and the habitat changes. It's then the leopards' area, and they co-exist without really any major problems.

“The ecosystem changes once the sun goes down. People came up to us, wanted to know, ‘What are you doing here?’ I told them and showed them some of the footage and images we were getting. They had lived there for ten years and didn’t even know the leopards were there, as close as from me to you, and yet have zero problems with them. A guy got up in the middle of the night one night, looked out his windows, and for the first time in ten years, he sees this leopard on a bridge. They are happy about it, too.They want to live with these animals because they don’t find that there’s any conflict.”

There are more mountain lions in the coastal Los Angeles area than people might suppose, Winter added. “There’s a healthy population of mountain lions in the Santa Monica Recreational Area, between, like, Sunset and a little further north. There are probably 15 or 20 cats in all.”

Mountain lions are just as secretive around people as leopards. P22 is native to Griffith Park, site of the famous Griffith Observatory.

“In all the months I spent in Griffith Park, I never met anybody who saw the mountain lion,” Winter said. “I never saw the mountain lion there. They don’t want to be seen, and they have plenty to eat there. So they’re comfortable.”

Wild animals getting along with people pre-supposes there aren’t any idiots — of the human kind — who will mess things up, Winter admitted.

“The mountain lion doesn’t want to be seen. That’s the bottom line. The leopard is the most adaptable cat in the world, as far as I’m concerned. They are secretive, and they don’t want any interaction. But as far as the idiot part goes, that’s, well . . . who knows?”