Almost as well-known for his dedication to environmental causes as he is for his acting, Leonardo DiCaprio does much more than pay lip service to the crucial issues concerning the planet. "Why is it important to me? It's important to everybody," he replied when MNN asked about it at the news conference for his latest film, the Clint Eastwood-directed "J. Edgar."

"The environmental movement is the biggest peoples' movement in the world. Unfortunately, our governments and corporations haven't responded to protect our planet's natural resources," said DiCaprio, whose interests were first sparked in childhood. "I was fascinated with nature and I actually wanted to be a marine biologist when I was very young and that was a great passion of mine. In the off-season when I'm not making movies, I became more and more active as an environmentalist and trying to be more vocal about issues that I felt were important. I created my foundation as a result of that and throughout my website I try to shed some light on some very topical issues. "Right now the campaign that I'm a part of is to save the last remaining wild tigers throughout Asia. There are only 3,200 left in the wild.  There are more tigers in Texas in cages than there are tigers in the wild and we're at risk of losing this iconic species for all time."

DiCaprio explained that the problem is twofold. "Throughout Asia, a lot of these countries are selling off their jungle and forest rights to palm oil and paper and pulp companies, and there's this [idea] that comes from witch doctors that these animals can make you more virile, make you more of a man, so they crush the bones and make wine out of them. Unfortunately, the wild tiger's is the most expensive and sought after," he said, noting that a similar belief has led to slaughter of rhinoceros for their horns and sharks for their fins. "They think it has medicinal properties. That kind of mentality needs to be changed." At the same time, "it's a land preservation effort, because if you can unify the public behind saving an iconic species like the tiger like they did with the panda, it means you need to protect their habitat and that means saving thousands of acres for them to be able to roam and breed. So there's a huge effort throughout Asia to protect the habitat," said DiCaprio, who is working with savetigersnow.org and the World Wildlife Fund on the issue.  

A member of the WWF board (ditto the NRDC, Global Green and the International Fund for Animal Welfare), he hopes that the initiative will be as successful as the "great victory" for which he campaigned, a prohibition on shark finning. "We have a ban in California that's going to save a lot of these top predators in the ocean," he said. "The idea is to get people to become more knowledgeable about the issue and try to get corporations and individuals to contribute to these nonprofit organizations to make that happen."

On screen, the star of such iconic films as "Titanic," "The Aviator," "The Departed" and "Inception" plays what is arguably his most challenging role yet, aging over six decades to portray the life and career of FBI founder J. Edgar Hoover in "J. Edgar," opening Nov. 9 in New York, Los Angeles, Chicago, San Francisco and Washington D.C., and in more cities on Nov. 11.

Hoover is not a likeable character, but DiCaprio succeeds in bringing him to life in all his contradictions and complexities. "I don't have to sympathize or empathize with a human being in order to portray them. Some of the greatest roles that actors have been able to play haven't been the most endearing on screen," reminded the actor, who credits screenwriter Dustin Lance Black's script for its "fascinating portrait" of a man who devoted his life to government service while denying himself a personal life, but undeniably accomplished much in the process.

"J. Edgar Hoover really transformed the police system in America and created this federal bureau that to this day is one of the most feared and respected and revered police forces in the entire world. But in his later years he became, in essence, a political dinosaur who didn't adapt to the changing of our country. When the Civil Rights Movement came along, he saw that as an uprising of the people and didn't adapt or change. He stayed in power way too long and he didn't listen to his own critics. You can't deny that he was a patriot, but at the same time, his tactics were pretty deplorable."

The film explores Hoover's relationships with his right-hand man Clyde Tolson (Armie Hammer), his loyal secretary Helen Gandy (Naomi Watts) and his mother (Judi Dench), with whom he lived until she died. "He was a crockpot of eccentricities. We couldn't even fit all his eccentricities into this movie," quipped DiCaprio, "One of the most powerful men in our country lived with his mother until he was 40 years old, and listened to his mother for political advice. He was a mama's boy."

Also depicted is the homosexuality that was suspected but never stated. Hoover "was incredibly oppressed emotionally. His only outlet was his job. No matter what his sexual orientation was, he was devoted to his job and power was paramount to him. Holding onto that power at all costs was the most important thing in his life. He should have retired much sooner than he did and many presidents tried to oust him," DiCaprio reflected. "He didn't adapt or change to our country and that's one of the most important things that a political leader can do."

DiCaprio relished delving into researching Hoover and talking to people who knew him on a visit to Washington, D.C., comparing the process to "a college course on J. Edgar Hoover. That's the fun of making a movie for me, not only understanding the history and reading the books, but understanding what motivated this man was the most fascinating part of this research."

Fortuitously, added DiCaprio, Eastwood saved the scenes involving the elderly versions of the characters for the final two weeks of filming "so we got to prepare for that and get our footing in our characters. We sat in the makeup chair for five or six or seven hours. But the challenge for me was not just the prosthetic work and how to move like an older man, but how to have 50 years of experience in the workplace and how to talk to a young Robert Kennedy as if he was some political upstart that didn't know what he was talking about."

DiCaprio praised director Eastwood for making that job as easy as possible. "Clint creates an environment for all of us to really focus on the acting and the drama and the interaction of the characters. He expects you to plant your feet and tell the truth and that's what we tried our best to do on this movie. He was very understanding about the different time periods that we had to shift back and forth from in this movie, all the complex politics and character development, and he gave us everything we could possibly ask for as actors."

DiCaprio is currently working with director Baz Luhrmann on a new version of "The Great Gatsby," playing the title character opposite Carey Mulligan as Daisy Buchanan and Tobey Maguire as Nick Carraway.

Photo: Keith Bernstein/Warner Bros.

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